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Contents Wiring diagrams Section: Exterior Lights All sections

Lighting System Cadillac SRX II

Exterior Lights 65 illustrations ~44566 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Brake Pedal Position Sensor Bolt9 N.m80 lb in
Fog Lamp Assembly Screws2.5 N.m22 lb in
Headlamp Control Module Nuts6 N.m53 lb in
Headlamp Leveling Front Suspension Height Sensor Fastener8 N.m71 lb in
Headlamp Leveling Rear Suspension Height Sensor Fastener8 N.m71 lb in
Headlamp Screws6 N.m53 lb in
High Mounted Stop Lamp to the Rear End Spoiler Screws2 N.m18 lb in
Light Plate Blocker Bolts2.5 N.m22 lb in
Rear Bracket Compartment Frame Bolts9 N.m80 lb in
Rear Bracket Compartment Frame Nuts9 N.m80 lb in
Tail Lamp to the Body Panel Screws2.5 N.m22 lb in
Trailer Lamp Control Module Bolt9 N.m80 lb in

Scheme 1

Scheme 1: Headlights/Daytime Running Lights (DRL) Schematics
Scheme 1: Headlights/Daytime Running Lights (DRL) Schematics

Scheme 2

Scheme 2
Scheme 2

Scheme 3

Scheme 3
Scheme 3

Scheme 4

Scheme 4
Scheme 4

Scheme 5

Scheme 5
Scheme 5

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7: Fog Lights Schematics
Scheme 7: Fog Lights Schematics

Scheme 8

Scheme 8: Exterior Lights Schematics
Scheme 8: Exterior Lights Schematics

Scheme 9

Scheme 9
Scheme 9

Scheme 10

Scheme 10
Scheme 10

Scheme 11

Scheme 11
Scheme 11

Scheme 12

Scheme 12
Scheme 12

Scheme 13

Scheme 13: Interior Lights Schematics
Scheme 13: Interior Lights Schematics

Scheme 14

Scheme 14
Scheme 14

Scheme 15

Scheme 15: Interior Lights Dimming Schematics
Scheme 15: Interior Lights Dimming Schematics

Scheme 16

Scheme 16
Scheme 16

Scheme 17

Scheme 17
Scheme 17

DIAGNOSTIC CODE INDEX

DTCDescription
DTC B0655B0655 5A: Brake Lamp Switch Circuit Not Plausible
DTC B096AB096A 02: Hazard Lamps Switch Backlight Circuit Short to Ground
DTC B1405, B1529, or B257BB1405 02: Control Module Voltage Reference Output 2 Circuit Short to Ground B1405 03: Control Module Voltage Reference Output 2 Circuit Low Voltage B1405 07: Control Module Voltage Reference Output 2 Circuit High Voltage B1529 03: Control Module Voltage Reference Output 5 Circuit Low Voltage B1529 07: Control Module Voltage Reference Output 5 Circuit High Voltage B257B 03: Lighting Control Switch Signal Low Voltage B257B 07: Lighting Control Switch Signal High Voltage
DTC B1480B1480 02: Battery Rundown Protection Circuit Short to Ground
DTC B2530B2530 02: Front Fog Lamps Control Circuit Short to Ground
DTC B2540B2540 02: Rear Fog Lamps Control Circuit Short to Ground
DTC B2545B2545 01: Backup Lamps Circuit Short to Battery B2545 02: Backup Lamps Circuit Short to Ground B2545 04: Backup Lamps Circuit Open
DTC B256AB256A 02: Liftgate Lamp Control Circuit Short to Ground
DTC B2575 or B2699B2575 01: Left Headlamp Control Circuit Short to Battery B2575 02: Left Headlamp Control Circuit Short to Ground B2575 04: Left Headlamp Control Circuit Open B2699 01: Right Headlamp Control Circuit Short to Battery B2699 02: Right Headlamp Control Circuit Short to Ground B2699 04: Right Headlamp Control Circuit Open
DTC B257AB257A 00: Headlamp Switch Input Signals Correlation Malfunction
DTC B257BB257B 03: Lighting Control Switch Signal Low Voltage B257B 07: Lighting Control Switch Signal High Voltage
DTC B257C or B257DB257C 00: Left Headlamp Assembly Malfunction B257D 00: Right Headlamp Assembly Malfunction
DTC B2580B2580 02: High Beam Control Circuit Short to Ground
DTC B2585 or B3867B2585 02: Park Lamps Control Circuit Short to Ground B3867 02: Right Park Lamp Control Circuit Short to Ground
DTC B258AB258A 01: Low Beam Control Circuit Short to Battery B258A 02: Low Beam Control Circuit Short to Ground B258A 04: Low Beam Control Circuit Open
DTC B2600 or B2605B2600 01: Left Daytime Running Lamps Control Circuit Short to Battery B2600 02: Left Daytime Running Lamps Control Circuit Short to Ground B2600 04: Left Daytime Running Lamps Control Circuit Open B2605 01: Right Daytime Running Lamps Control Circuit Short to Battery B2605 02: Right Daytime Running Lamps Control Circuit Short to Ground B2605 04: Right Daytime Running Lamps Control Circuit Open
DTC B260AB260A 00: Backlight and Display Dimming Request Circuit Malfunction
DTC B260B or B260CB260B 01: Left Daytime Running Lamp Relay Control Circuit Short to Battery B260B 02: Left Daytime Running Lamp Relay Control Circuit Short to Ground B260B 04: Left Daytime Running Lamp Relay Control Circuit Open B260C 01: Right Daytime Running Lamp Relay Control Circuit Short to Battery B260C 02: Right Daytime Running Lamp Relay Control Circuit Short to Ground B260C 04: Right Daytime Running Lamp Relay Control Circuit Open
DTC B260D or B260EB260D 01: Left Daytime Running Lamp and Front Park Lamp Control Circuit Short to Battery B260D 02: Left Daytime Running Lamp and Front Park Lamp Control Circuit Short to Ground B260D 04: Left Daytime Running Lamp and Front Park Lamp Control Circuit Open B260E 01: Right Daytime Running Lamp and Front Park Lamp Control Circuit Short to Battery B260E 02: Right Daytime Running Lamp and Front Park Lamp Control Circuit Short to Ground B260E 04: Right Daytime Running Lamp and Front Park Lamp Control Circuit Open
DTC B2615B2615 02: Passenger Compartment Dimming 2 Circuit Short to Ground
DTC B2625B2625 02: Display Dimming Pulse Width Modulation Output Circuit Short to Ground
DTC B2645B2645 03: Ambient Light Sensor Circuit Low Voltage B2645 07: Ambient Light Sensor Circuit High Voltage
DTC B2652B2652 02: Passenger Compartment Dimming 3 Circuit Short to Ground
DTC B2657B2657 02: Ignition Switch Halo Lamp Circuit Short to Ground
DTC B2740B2740 00: Front Fog Lamp Switch Circuit Malfunction
DTC B3410 or B3420B3410 01: Automatic Headlamp Leveling Control Module Front Axle Sensor Signal Circuit Short to Battery B3410 06: Automatic Headlamp Leveling Control Module Front Axle Sensor Signal Circuit Low Voltage/Open B3420 01: Automatic Headlamp Leveling Control Module Rear Axle Sensor Signal Circuit Short to Battery B3420 06: Automatic Headlamp Leveling Control Module Rear Axle Sensor Signal Circuit Low Voltage/Open
DTC B3415B3415 01: Automatic Headlamp Leveling Control Module Axle Sensor Supply Circuit Short to Battery B3415 02: Automatic Headlamp Leveling Control Module Axle Sensor Supply Circuit Short to Ground
DTC B3588B3588 00: Rear Fog Lamp Switch Circuit Malfunction
DTC B3596B3596 00: Hazard Lamps Request Circuit
DTC B364AB364A 00: Surveillance Mode Switch Circuit Malfunction
DTC B3650B3650 08: High Beam Request Signal Circuit Performance - Signal Invalid
DTC B3806B3806 00: High Beam and Headlamp Flash Select Circuit Malfunction
DTC B3881 or B3882B3881 02: Tail Lamp Circuit Short to Ground B3881 04: Tail Lamp Circuit Open B3882 02: Right Tail Lamp Circuit Short to Ground B3882 04: Right Tail Lamp Circuit Open
DTC B3883B3883 02: License Plate Lamp Circuit Short to Ground B3883 04: License Plate Lamp Circuit Open
DTC B3884B3884 02: Center High Mounted Brake Lamp Circuit Short to Ground B3884 04: Center High Mounted Brake Lamp Circuit Open
DTC B3885 or B3886B3885 02: Trailer Left Tail Lamp Circuit Short to Ground B3885 04: Trailer Left Tail Lamp Circuit Open B3886 02: Trailer Right Tail Lamp Circuit Short to Ground B3886 04: Trailer Right Tail Lamp Circuit Open
DTC B3887 or B3888 (With U4G)B3887 02: Trailer Left Turn Signal Circuit Short to Ground B3887 04: Trailer Left Turn Signal Circuit Open B3888 02: Trailer Right Turn Signal Circuit Short to Ground B3888 04: Trailer Right Turn Signal Circuit Open
DTC B3887 or B3888 (Without U4G)B3887 02: Trailer Left Turn Signal Circuit Short to Ground B3887 04: Trailer Left Turn Signal Circuit Open B3888 02: Trailer Right Turn Signal Circuit Short to Ground B3888 04: Trailer Right Turn Signal Circuit Open
DTC B3889B3889 02: Trailer Brake Lamps Circuit Short to Ground B3889 04: Trailer Brake Lamps Circuit Open
DTC B388AB388A 01: Trailer Park Lamps Circuit Short to Battery B388A 02: Trailer Park Lamps Circuit Short to Ground B388A 04: Trailer Park Lamps Circuit Open
DTC B3890B3890 02: Trailer Backup Lamps Circuit Short to Ground B3890 04: Trailer Backup Lamps Circuit Open
DTC B3891B3891 02: Trailer Fog Lamps Circuit Short to Ground B3891 04: Trailer Fog Lamps Circuit Open
DTC B3948 or B3949B3948 02: Left Front Turn Signal Circuit Short to Ground B3949 02: Right Front Turn Signal Circuit Short to Ground
DTC B3950 or B3951B3950 02: Left Rear Turn Signal Circuit Short to Ground B3951 02: Right Rear Turn Signal Circuit Short to Ground
DTC C0277 or C0890C0277 06: Brake Pedal Position Sensor Circuit Short to Ground or Open C0277 07: Brake Pedal Position Sensor Circuit High Voltage C0277 09: Brake Pedal Position Sensor Circuit Too Fast Transitions C0277 4B: Brake Pedal Position Sensor Circuit Calibration Not Learned C0890 03: Control Module Voltage Reference Output 3 Circuit Low Voltage C0890 07: Control Module Voltage Reference Output 3 Circuit High Voltage
DTC C0297C0297 02: Brake Applied Output Circuit Short to Ground

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Diagnostic Fault Information

CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Center High Mounted Brake Lamp ControlB3884 02B3884 041B0655 5A
1. Center High Mounted Brake Lamp Always ON

Circuit/System Description

The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an analog voltage signal to the body control module (BCM). The BCM will apply battery voltage to the right, left and center stop lamp control circuits and to the trailer brake control module if equipped.

Conditions for Running the DTC

When the brake pedal is applied.

Conditions for Setting the DTC

The trailer brake control module receives a serial data message from the BCM that the brakes have been applied, but the trailer brake control module does not detect a signal voltage on the center high mounted stop lamp control circuit.

Action Taken When the DTC Sets

The brake lights on the trailer will be inoperative

Conditions for Clearing the DTC

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Reference Information

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Observe the function of the E6 center high mounted stop lamp while pressing and releasing the brake pedal. The E6 center high mounted stop lamp should turn ON when the pedal is pressed and OFF when the pedal is released.

  1. If the E6 center high mounted stop lamp is always ON or always OFF, refer to «Stop Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. If the E6 center high mounted stop lamp turns ON and OFF as commanded, perform the Circuit/System Testing.

Circuit/System Testing

  1. Ignition OFF, disconnect the X1 harness connector at the K67 trailer brake control module.
  2. Connect a test lamp between the signal circuit terminal 14 and ground.
  3. Ignition ON, command the Center Brake Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF while changing between the commanded states. If the test lamp is always ON, test the signal circuit for a short to voltage. If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance.
  4. If all circuits test normal, replace the K67 trailer brake control module.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for trailer brake control module replacement, programming and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Interior Backlighting ControlB096A 0221
1. Hazard Backlighting at Full Intensity and Cannot be Dimmed 2. Hazard Backlighting do Not Illuminate

The body control module (BCM) supplies a voltage reference through the instrument panel cluster dimming voltage reference circuit to the instrument panel cluster lamps dimmer switch, which is part of the headlamp switch. When the dimmer switch is placed in a desired brightness position, reference voltage is applied through the dimmer switch rheostat and the cluster lamps dimmer switch signal circuit to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage to the LED dimming supply circuit to all related interior lamps, illuminating them to the desired level of brightness.

The ignition is ON.

B096A 02

The BCM detects a short to ground on the LED backlight lamp control circuit.

The BCM will not dim or illuminate any LED backlighting supplied by the backlight lamp control circuits.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 100 consecutive malfunction ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, vary the interior backlighting from dim to full bright by using the dimmer switch. The interior backlighting should dim and then become full bright.

  1. Ignition OFF, disconnect the harness connector at the S26 Hazard Lamps Switch.
  2. Test for less than 5 ohms between the ground circuit terminal 1 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the backlight control circuit of the S26 Hazard Lamps Switch terminal 5 and ground.
  4. Ignition ON, vary the interior lamp dimming switch from dim to full bright. The test lamp should dim and then become full bright. If the test lamp cannot be dimmed, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module. If the test lamp is always OFF, test the control circuit for open/high resistance or short to ground. If the circuit tests normal, replace the K9 Body Control Module.
  5. If all circuits test normal, replace the S26 Hazard Lamps Switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Radio Control Assembly Replacement»(/cadillac/srx/ii-2009-2012/remont/entertainment-systems/#cellular-systems-entertainment-systems-navigation-systems)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Switch B+B1405 03, B1529 03, B257B 03, 1B257B 03, 1
Instrument Panel Lamps Dimmer Switch SignalB257B 03, 1B257B 03, 1B257B 07
Interior Backlighting Control BCM Terminal 9 X7B2625 0221
Interior Backlighting Control BCM Terminal 8 X2B2625 02, 221
Interior Backlighting Control BCM Terminal 5 X1 (with UD5)B2625 0221
Headlamp Switch GroundB257B 03
1. Interior backlighting at full intensity and cannot be dimmed 2. Interior backlighting component does not illuminate

The body control module (BCM) supplies battery positive voltage to the backlight dimmer switch, which is part of the headlamp switch. When the backlight dimmer switch is placed in a desired brightness position, reference voltage is applied to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage to the LED dimming supply circuit to all related interior lamps, illuminating them to the desired level of brightness.

The ignition is ON.

B1405 03, B1529 03, or B257B 03

The BCM detects less than 0.3 V on the dimmer switch signal circuit.

B1405 07, B1529 07, or B257B 07

The BCM detects a voltage greater than 12.2 V on dimmer switch signal circuit.

The BCM will not dim or illuminate any LED backlighting supplied by the backlight lamp control circuits.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 100 consecutive fault free ignition cycles have occurred.

Schematic Reference

  1. «Interior Lights Dimming Schematics»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Steering Wheel Secondary/Configurable Control Schematics»(/cadillac/srx/ii-2009-2012/remont/memory-modules/#configurable-customer-control-system)

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, headlamps ON, vary the interior backlight dimming from low to full bright by using the dimmer switch. The interior backlighting should start dim and then become full bright.

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Test for less that 10 ohms between the ground circuit terminal 6 and ground. If greater than the specified range, test the ground circuit for an open high/resistance.
  3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. Ignition ON, test for less than 0.3 V between signal circuit terminal 12 and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the B+ circuit terminal 1. The interior backlighting should be dimmed. If the interior backlighting is not dimmed, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. If all circuits test normal, test or replace the S30 headlamp switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Battery Saver Relay - Control CircuitB1480 02

The battery saver mode reduces the parasitic load of some modules during overseas shipment or during vehicle storage conditions. This improves the drain time on the battery of up to 70 days without the battery going dead. When the vehicle is in transport/storage, some features may have reduce functionality as a result being in the battery saver mode, such as disabling the Remote Function Actuator or content theft features.

The battery saver mode incorporates a latching relay that when enabled disconnects some modules from their ignition off power or memory power sources. Battery saver mode is initiated by starting the vehicle and then turning the ignition key into the crank position for greater than 15 seconds. The mode is disengaged by repeating the previous process causing the relay to latch in the other direction. This feature can be used as many times as necessary if the vehicle is to be stored for an extended period of time.

  1. The system voltage is between 9-16 V.
  2. The DTC can only run when the output is activated.

The BCM detects a short to ground in the battery saver relay set circuit.

The module output driver will be shut down and not supply voltage to the battery saver relay set circuit.

  1. The current DTC will clear when the module request for the output is removed or the malfunction is no longer present.
  2. A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Schematic Reference

  1. «Body Control System Schematics»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#data-communication-system)
  2. «Power Distribution Schematics»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-wiring-schematics-and-wiring-harness-routing-diagrams)

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition OFF, disconnect the KR104A battery saver relay.
  2. Connect a test lamp between the relay control circuit and ground.
  3. Enable and disable the batter saver mode. The test lamp should turn ON and OFF when changing the relay latch positions. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, test or replace the KR104A battery saver relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Relay Replacement (Attached to Wire Harness)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Front Fog Lamps ControlB2530 0221
1. Front Fog Lamps Always ON 2. Front Fog Lamps Inoperative

The front fog lamp relay is supplied with battery voltage at all times. The front fog lamp switch signal circuit is grounded momentarily by pressing the front fog lamp switch. The body control module (BCM) energizes the front fog lamp relay by applying ground to the front fog lamp relay control circuit. When the front fog lamp relay is energized, the relay switch contacts close and battery voltage is applied through the front fog lamp fuse to the front fog lamp supply voltage circuit which illuminates the front fog lamps.

Front fog lamps activated

The BCM detects a short to ground on the front fog lamp relay control circuit.

The front fog lamps will always be illuminated.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Ignition ON, command the Fog Lamps ON and OFF with a scan tool. The front fog lamps should turn ON and OFF when changing between the commanded states.

  1. Ignition OFF, disconnect the X5 harness connector at the K9 BCM.
  2. Ignition ON, test for greater than 10V between the control circuit terminal 10 and ground. If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50A underhood fuse block.
  3. If all circuits test normal, replace the K9 BCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Fuse Block Replacement»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Rear Fog Lamps ControlB2540 0221
Tail Lamp Ground2
1. Rear fog lamp always ON 2. Rear fog lamp always OFF

The body control module (BCM) energizes the rear fog lamp by applying voltage to the rear fog lamp control circuit. When the rear fog lamp control circuit is energized the rear fog lamp is illuminated.

Rear fog lamp activated

The BCM detects a short to ground on the rear fog lamp control circuit.

The rear fog lamp will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the Rear Fog Lamp(s) Relay ON and OFF with a scan tool. The rear fog lamp should turn ON and OFF when changing between the commanded states.

  1. Ignition OFF, disconnect the harness connector at the E5 fog lamp-rear.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal A and ground.
  4. Ignition ON, command the Rear Fog Lamp(s) Relay ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the E5 fog lamp-rear.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Tail Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
BCM B+1, 21, 2
Backup Lamp Supply VoltageB2545 02B2545 04B2545 01
Left Backup Lamp Ground1
Right Backup Lamp Ground2
1. Left Backup Lamp Inoperative 2. Right Backup Lamp Inoperative

When the engine is running and the transmission is placed in reverse gear, the transmission control module sends a serial data message to the body control module (BCM). The message indicates that the gear selector is in the reverse position. The BCM applies battery voltage to the backup lamps. Once the driver moves the gear selector out of the reverse position, a message is sent by the transmission control module via serial data requesting the BCM to remove battery voltage from the backup lamp signal circuit. The BCM will not apply battery voltage to the backup lamps if the engine is not running.

Reverse Gear engaged.

B2545 01

The BCM detects a short to voltage on the backup lamps control circuit.

B2545 02

The BCM detects a short to ground on the backup lamps control circuit.

B2545 04

The BCM detects an open/high resistance both backup lamps control circuits.

For B2545 01, both backup lamps will be continuously illuminated.

For B2545 02 and B2545 04, both backup lamps will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Engine running, command the Backup Lamps ON and OFF with a scan tool. The E5A backup lamp-left and the E5B backup lamp-right should turn ON and OFF when changing between the commanded states.

  1. If the E5A backup lamp-left or the E5B backup lamp-right is always OFF, inspect for a burned out bulb or corrosion of the bulb sockets.
  1. If the E5A backup lamp-left and the E5B backup lamp-right are always OFF or always ON, perform the Circuit/System Testing.
  1. Ignition OFF, disconnect the X2 harness connector K9 BCM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the X2 harness connector K9 BCM
  4. Disconnect the harness connector at the E5A backup lamp listed below: X3 harness connector E5E tail lamp-left (Without T79) X1 harness connector E5E tail lamp-left (With T79) X3 harness connector E5F tail lamp-right (Without T79) X1 harness connector E5F tail lamp-right (With T79)
  5. Test for less than 30 ohms between the ground circuit terminal listed below and ground. E5E tail lamp-left (Without T79) ground terminal 2 E5E tail lamp-left (With T79) ground terminal C E5F tail lamp-right (Without T79) ground terminal 2 E5F tail lamp-right (With T79) ground terminal C If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Connect a test lamp between the control circuit terminal listed below and ground: E5E tail lamp-left (Without T79) control terminal 1 E5E tail lamp-left (With T79) control terminal D E5F tail lamp-right (Without T79) control terminal 1 E5F tail lamp-right (With T79) control terminal D
  7. Engine running, command the Backup Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the selected states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  8. If all circuits test normal, test or replace the E5A backup lamp-left and the E5B backup lamp-right.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Backup Lamp Bulb Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Cargo Lamp ControlB256A 0221
Cargo Lamp Ground2
1. Cargo Lamp Always ON 2. Cargo Lamp Always OFF

When the body control module (BCM) receives a liftgate open signal, the BCM supplies B+ to the cargo lamp control circuit. This will illuminate the cargo lamp.

  1. Ignition ON.
  2. The system voltage is between 9-16 V.

The BCM detects a short to ground on the cargo lamp control circuit.

The cargo lamps are inoperative.

A current DTC clears when the diagnostic runs and passes.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Command the Cargo Lamp ON and OFF with a scan tool. The cargo lamps should turn ON and OFF when changing between the commanded states.

  1. Ignition OFF, disconnect the harness connector at the appropriate cargo lamp.
  2. Test for less than 5 ohms between the ground circuit terminal 2 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal 1 and ground.
  4. Command the Cargo Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to round or open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the cargo lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Rear Compartment Courtesy Lamp Replacement - Liftgate»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Rear Compartment Courtesy Lamp Replacement - Quarter Upper Trim»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
BCM B+B2575 04B2575 04
BCM B+B2699 02B2699 02
Left Headlamp ControlB2575 02B2575 04B2575 01
Right Headlamp ControlB2699 02B2699 04B2699 01

When the headlight switch is placed in low beam position, the body control module (BCM) applies a voltage to the low beam headlamps through their respective voltage supply circuits.

The headlamps are turned ON.

B2575 01

The BCM detects a short to voltage on the left headlamp low beam control circuit.

B2575 02

The BCM detects a short to ground on the left headlamp low beam control circuit.

B2575 04

The BCM detects an open on the left headlamp low beam control circuit or an open/high resistance on the left headlamp low beam ground circuit.

B2699 01

The BCM detects a short to voltage on the right headlamp low beam control circuit.

B2699 02

The BCM detects a short to ground on the right headlamp low beam control circuit.

B2699 04

The BCM detects an open on the right headlamp low beam control circuit or an open/high resistance on the right headlamp low beam ground circuit.

For B2575 02, B2575 04, B2699 02 or B2699 04, the appropriate headlamp low beam will be inoperative.

For B2575 01 or B2699 01, the appropriate headlamp low beam will be continuously illuminated.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the E4G headlamp-left low beam and the E4F headlamp-right low beam while commanding the low beam lamps ON and OFF with a scan tool. The E4G headlamp-left low beam and the E4F headlamp-right low beam should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the harness X1 harness connector at the K9 BCM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal listed below and ground: B+ circuit terminal 3 B+ circuit terminal 4 If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the harness X1 harness connector at the K9 BCM.
  4. Disconnect the inline harness connector at the appropriate E4 headlamp-low beam listed below: E4G headlamp-left low beam X115 inline harness connector E4F headlamp-right low beam X116 inline harness connector
  5. Connect a test lamp between the control circuit terminal G and ground.
  6. Ignition ON, command the low beam lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF while changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM
  7. If all circuits test normal, replace the headlamp bulb or the headlamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Switch Park Lamp Signal2B257A 002
Headlamp Switch On SignalB257A 0011
Headlamp Switch Headlamps Off SignalB257A 0011
Headlamp Switch Ground1
1. Headlight Auto Function Only 2. Headlight Auto Function Disabled

The body control module (BCM) monitors the 12 V signal circuits for the headlamps off signal, headlamps on signal and the park lamp on signal circuits. When the headlight control switch is selected to the desired headlamp function, the signal circuit is pulled to ground and the BCM will detect the voltage drop in that signal circuit and will command the appropriate lights to turn on or turn off.

The ignition is in the ON, ACCESSORY or RUN position.

The BCM receives an unexpected signal along either the headlamp switch OFF circuit or the headlamp ON circuit.

The automatic headlamps will malfunction.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool Headlamps On Switch, Park Lamps Switch and Automatic Headlamps Disable Switch parameters while selecting the headlamp control switch between the Off, park lamps and headlamps settings. Each parameter should be Inactive and change to Active as each setting is selected.

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Ignition OFF, test for less than 30 ohms between the ground circuit terminal 6 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Park Lamps Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 3 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  4. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the ground circuit terminal 6. Verify the scan tool Park Lamps Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. Verify the scan tool Headlamps On Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  6. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the ground circuit terminal 6. Verify the scan tool Headlamps On Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  7. Verify the scan tool Automatic Headlamps Disable Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 5 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  8. Install a 3 A fused jumper wire between the signal circuit terminal 5 and the ground circuit terminal 6. Verify the scan tool Automatic Headlamps Disable Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  9. If all circuits test normal, test or replace the S30 headlamp switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Switch B+ ReferenceB257B 03*B257B 03*
Instrument Panel Lamps Dimmer Switch SignalB257B 03*B257B 03*B257B 07*
* Interior backlighting at full intensity and cannot be dimmed

The body control module (BCM) supplies a reference voltage to the backlight dimmer switch, which is part of the headlamp switch. When the backlight dimmer switch is placed in a desired brightness position, reference voltage is applied to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage to the LED dimming supply circuit to all related interior lamps, illuminating them to the desired level of brightness.

The ignition is ON.

B257B 03

The BCM detects a voltage that is lower than 0.3 V on the dimming voltage circuit.

B257B 07

The BCM detects a voltage that is greater than 12.2 V on dimming voltage circuit.

The BCM will not dim or illuminate any LED backlighting supplied by the backlight lamp control circuits.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 100 consecutive malfunction ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, headlamps ON, vary the interior backlight dimming from low to full bright by using the dimmer switch. The interior backlighting should start dim and then become full bright.

  1. Ignition OFF, disconnect the harness connector at the S30 Headlamp Switch.
  2. Ignition ON, test for B+ between the B+ reference circuit terminal 1 and ground. If less than the specified range, test the B+ reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  3. Ignition ON, test for less than 0.3 V between signal circuit terminal 12 and ground. If greater than the specified range, test the signal circuit terminal 12 for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  4. Reconnect the harness connector at the S30 Headlamp Switch.
  5. Dim the interior backlighting with the S30 Headlamp Switch.
  6. Disconnect the harness connector at the S30 Headlamp Switch.
  7. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the B+ reference circuit terminal 1. The interior backlighting should now be dimmed. If the interior backlighting is not dimmed, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  8. If all circuits test normal, replace the S30 Headlamp Switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Headlamp Low Beam Supply VoltageB257C 00B257C 00B257C 00
Right Headlamp Low Beam Supply VoltageB257D 00B257D 00B257D 00

The headlamp control module calculates the headlamp angle and sends commands to the left and right adaptive forward lighting system headlamp actuators. The headlamp actuators drive the headlamps to the position commanded by the headlamp control module. The headlamp control module monitors the headlamp actuator motor control circuits for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored in memory and the driver will be notified with a message displayed over the driver information center located on the instrument cluster.

The headlamps are turned ON.

B257C 00

The headlamp control module detects a fault in the left low beam control circuit or an open/high resistance is the left low beam ground circuit.

B257D 00

The headlamp control module detects a fault in the right low beam control circuit or an open/high resistance is the right low beam ground circuit.

The appropriate headlamp is inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the low beam headlamps while commanding the Low Beam Lamps ON and OFF with a scan tool. The E4G headlamp-left low beam and the E4H headlamp-right low beam should turn ON and OFF while changing between the commanded states.

  1. If the E4G headlamp-left low beam is always OFF, refer to «Left Low Beam Inoperative»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__left-low-beam-inoperative) .
  1. If the E4H headlamp-right low beam is always OFF, refer to «Right Low Beam Inoperative»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__right-low-beam-inoperative) .
  1. If both low beam headlamps are always ON or always OFF, refer to Headlamps Malfunction below.

Left Low Beam Inoperative

  1. Ignition OFF, disconnect the X118 inline harness connector at the E4G headlamp-left low beam.
  2. Connect a test lamp between the control circuit terminal G and ground.
  3. Ignition ON, command the Low Beam Lamps ON with a scan tool, the test should illuminate while commanding the headlamp ON. If the test lamp does not illuminate and the circuit fuse is good, test the control circuit for an open/high resistance. If the test lamp does not illuminate and the circuit fuse is open, test the control circuit for a short to ground.
  4. If all circuits test normal, replace the E4G headlamp-left low beam.

Right Low Beam Inoperative

  1. Ignition OFF, disconnect the X120 inline harness connector at the E4H headlamp-right low beam.
  2. Connect a test lamp between the control circuit terminal G and ground.
  3. Ignition ON, command the Low Beam Lamps ON with a scan tool, the test should illuminate while commanding the headlamp ON. If the test lamp does not illuminate and the circuit fuse is good, test the control circuit for an open/high resistance. If the test lamp does not illuminate and the circuit fuse is open, test the control circuit for a short to ground.
  4. If all circuits test normal, replace the E4H headlamp-right low beam.

Headlamps Malfunction

  1. Ignition OFF, disconnect the KR49 headlamp low beam relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 30 and ground. If the test lamp illuminates, test the control circuit for a short to voltage
  3. Verify that a test lamp illuminates between the B+ circuit terminal 87 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance
  4. Verify that a test lamp illuminates between the B+ circuit terminal 86 and ground. If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  5. Connect a 15A fused jumper wire between the B+ circuit terminal 87 and the control circuit terminal 30. Verify the E4G headlamp-left low beam and the E4H headlamp-right low beam are activated. If the E4G headlamp-left low beam and the E4H headlamp-right low beam do not activate, test the control circuit for a short to ground or an open/high resistance.
  6. Connect a test lamp between the B+ circuit terminal 86 and the control circuit terminal 85.
  7. Ignition ON, command the Low Beam Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  8. If all circuits test normal, test or replace the KR49 headlamp low beam relay.

Relay Test

  1. Ignition OFF, disconnect the KR49 headlamp low beam relay.
  2. Test for 60-180 ohms between terminals 85 and 86. If not within the specified range, replace the KR49 headlamp low beam relay.
  3. Test for infinite resistance between the following terminals: 30 and 86 30 and 87 30 and 85 85 and 87 If not the specified value, replace the KR49 headlamp low beam relay.
  4. Install a 15A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87. If greater than the specified range, replace the KR49 headlamp low beam relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Relay Replacement (Attached to Wire Harness)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for headlamp control module replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp High Beam Relay ControlB2580 0221
1. High Beam Lamps Always ON 2. High Beam Lamps Inoperative

The headlamp high beam relay is supplied with battery voltage at all times. The turn signal/multifunction switch signal circuit is grounded by pressing the turn signal/multifunction switch. The body control module (BCM) energizes the headlamp high beam relay by applying ground to the headlamp high beam relay control circuit. When the headlamp high beam relay is energized, the relay switch contacts close and battery voltage is applied through the high beam lamp fuses to the high beam lamp supply voltage circuit which illuminates the high beam lamps.

High beam lamps ON.

The BCM detects a short to ground in the headlamp high beam relay control circuit.

The high beam headlamps will always be illuminated.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the High Beams ON and OFF with a scan tool. The high beam headlamps should turn ON and OFF when changing between the commanded states.

  1. Ignition OFF, disconnect the X5 harness connector at the K9 BCM.
  2. Ignition ON, test for greater than 10V between the control circuit terminal 18 and ground. If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50A underhood fuse block.
  3. If all circuits test normal, replace the K9 BCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Fuse Block Replacement»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM, replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Park Lamps ControlB2585 0221
Right Park Lamps ControlB3867 0221
1. Park Lamps Always ON 2. Park Lamps Always OFF

The body control module (BCM) energizes the park lamps by applying voltage to the park lamp control circuit. When the park lamp control circuit is energized, the park lamps are illuminated.

Headlamp switch in park or low beam position.

B2585 02

The BCM detects a short to ground on the left side park lamp control circuit.

B3867 02

The BCM detects a short to ground on the right side park lamp control circuit.

The appropriate park lamps will be inoperative

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the function of the E2LF side marker lamp-left front, E5E tail lamp-left rear and the E4J park lamp-left front while commanding the Left Park Lamps ON and OFF with a scan tool. The E2LF side marker lamp-left front, E5E tail lamp-left rear and the E4J park lamp-left front should turn ON and OFF while changing between the commanded states If the E2LF side marker lamp-left front, E5E tail lamp-left rear and the E4J park lamp-left front are always ON or always OFF, refer to Left Side Marker/Tail Lamps Malfunction below.
  2. Ignition ON, observe the function of the E2RF side marker lamp-right front, E5F tail lamp-right rear and the E4K park lamp-right front while commanding the Right Park Lamps ON and OFF with a scan tool. The E2RF side marker lamp-right front, E5F tail lamp-right rear and the E4K park lamp-right front should turn ON and OFF while changing between the commanded states. If the E2RF side marker lamp-right front, E5F tail lamp-right rear and the E4K park lamp-right front are always ON or always OFF, refer to Right Side Marker/Tail Lamps Malfunction below.

Left Side Marker/Tail Lamps Malfunction

  1. Disconnect the X1 harness connector at the E5E tail lamp-left.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Disconnect the appropriate inline harness connector listed below: X111 inline harness connector (With TT6/TT7/TT8) X115 inline harness connector (Without TT6/TT7/TT8)
  4. Test for less than 30 ohms between the ground circuit terminal listed below and ground: Ground circuit terminal A Ground circuit terminal E If greater than the specified range, test the ground circuit for an open/high resistance.
  5. Connect a test lamp between the control circuit terminal listed below and ground. E2LF side marker lamp-left front control circuit terminal K E4J park lamp-left front control circuit terminal B E5E tail lamp-left control circuit terminal B
  6. Ignition ON, command the Left Park Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K9 BCM.
  7. If all the circuits test normal, replace the appropriate left marker lamp.

Right Side Marker/Tail Lamps Malfunction

  1. Disconnect the X1 harness connector at the E5F tail lamp-right.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition OFF, disconnect the appropriate inline harness connector listed below: X112 inline harness connector (With TT6/TT7/TT8) X116 inline harness connector (Without TT6/TT7/TT8)
  4. Test for less than 30 ohms between the ground circuit terminal listed below and ground: Ground circuit terminal A Ground circuit terminal E If greater than the specified range, test the ground circuit for an open/high resistance.
  5. Connect a test lamp between the control circuit terminal listed below and ground. E2RF side marker lamp-right front control circuit terminal K E4K park lamp-right front control circuit terminal B E5F tail lamp-right control circuit terminal A
  6. Ignition ON, command the Right Park Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K9 BCM.
  7. If all the circuits test normal, replace the appropriate right marker lamp

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Tail Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Low Beam Relay ControlB258A 02B258A 04B258A 01

When the headlight switch is placed in low beam position, the body control module (BCM) energizes the low beam headlamp relay which supplies battery voltage to the respective headlamp control circuits.

The headlamp switch is in the low beam position.

B258A 01

The BCM detects a short to voltage in the headlamp low beam relay control circuit.

B258A 02

The BCM detects a short to ground in the headlamp low beam relay control circuit.

B258A 04

The BCM detects an open/high resistance in the headlamp low beam relay control circuit.

B258A 01 or B258A 04

The low beam headlamps will be inoperative.

The low beam headlamps will be continuously illuminated.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the Headlamp Low Beam ON and OFF with a scan tool. The low beam lamp should turn ON and OFF when changing between the commanded states.

  1. Ignition OFF, disconnect the KR49 headlamp low beam relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 30 and ground. If the test lamp illuminates, test the control circuit for a short to voltage
  3. Verify that a test lamp illuminates between the B+ circuit terminal 87 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Verify that a test lamp illuminates between the B+ circuit terminal 86 and ground. If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  5. Connect a 15A fused jumper wire between the B+ circuit terminal 87 and the control circuit terminal 30. Verify the E4G headlamp-left low beam and the E4H headlamp-right low beam are activated. If the E4G headlamp-left low beam and the E4H headlamp-right low beam do not activate, test the control circuit for a short to ground or an open/high resistance.
  6. Connect a test lamp between the B+ circuit terminal 86 and the control circuit terminal 85.
  7. Ignition ON, command the Low Beam Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  8. If all circuits test normal, test or replace the KR49 headlamp low beam relay.
  1. Ignition OFF, disconnect the KR49 headlamp low beam relay.
  2. Test for 60-180 ohms between terminals 85 and 86. If not within the specified range, replace the KR49 headlamp low beam relay.
  3. Test for infinite resistance between the following terminals: 30 and 86 30 and 87 30 and 85 85 and 87 If not the specified value, replace the KR49 headlamp low beam relay.
  4. Install a 15A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87. If greater than the specified range, replace the KR49 headlamp low beam relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Relay Replacement (Attached to Wire Harness)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Daytime Running Lamps ControlB2600 02B2600 04B2600 01
Right Daytime Running Lamps ControlB2605 02B2605 04B2605 01

When the headlight switch is in the Auto position and the ambient light sensor detects sunlight, the body control module (BCM) will command the daytime running lamps to illuminate by providing 12 volts to the daytime running lamp control circuit.

  1. The engine is running.
  2. Headlamp switch in AUTO position.
  3. The ambient light is day.

B2600 01 or B2605 01

The BCM detects a short to voltage on the daytime running lamp control circuit

B2600 02 or B2605 04

The BCM detects a short to ground on the daytime running lamp control circuit

B2600 04 or B2605 04

The BCM detects an open/high resistance on the daytime running lamp control circuit

The daytime running lamp will be continuously illuminated.

B2600 02, B2600 04, B2605 02 or B2605 04

The daytime running lamp will be inoperative

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the Left Dedicated Daytime Running Lamp and the Right Dedicated Daytime Running Lamp ON and OFF with a scan tool. The E4C daytime running lamp - left and the E4D daytime running lamp - right should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the X1 harness connector K9 BCM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 3 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the X1 harness connector K9 BCM
  4. Ignition OFF, disconnect the inline harness connector listed below: E4C daytime running lamp - left X111 inline harness connector E4D daytime running lamp - right X116 inline harness connector
  5. Connect a test lamp between the control circuit terminal G and ground.
  6. Command the appropriate Dedicated Daytime Running Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K9 BCM.
  7. If all circuits test normal, replace the daytime running lamp bulb.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Backlight and Display Dimming Request SignalB260A

The body control module (BCM) supplies a reference voltage to the backlight dimmer switch, which is part of the headlamp switch. When the backlight dimmer switch is placed in a desired brightness position, reference voltage is applied through the backlight dimmer switch rheostat to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage to the LED dimming supply circuit to all related interior lamps, illuminating them to the desired level of brightness.

The ignition is ON. Parklamps are illuminated.

The BCM detects the instrument panel dimmer switch is ON for greater than 60 seconds.

The BCM will not dim or illuminate any LED backlighting supplied by the backlight lamp control circuits.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 100 consecutive malfunction ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, switch ON exterior lighting, vary the interior backlight from dim to full bright by using the dimmer switch. The interior backlighting should dim and then become full bright.

  1. Ignition OFF, disconnect the harness connector at the S30 Headlamp Switch.
  2. Ignition OFF, test for less than 5 ohms between the low reference circuit terminal 6 and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
  3. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 1 and ground. If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
  4. Verify the scan tool LED Backlight Dimming Command is less than 5 percent. If greater than the specified range, test the signal circuit terminal 12 for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
  5. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the 5 V reference circuit terminal 5. Verify the scan tool LED Backlight Dimming Command is greater than 95 percent. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
  6. If all circuits test normal, test or replace the S30 Headlamp Switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Daytime Running Lamp Relay B+B260B 04B260B 04
Right Daytime Running Lamp Relay B+B260C 04B260C 04
Left Daytime Running Lamp Relay ControlB260B 02B260B 04B260B 01
Right Daytime Running Lamp Relay ControlB260C 02B260C 04B260C 01
Daytime Running Lamp Relay Control221
1. The appropriate Park Lamp/Side Marker Lamp is Always ON 2. The appropriate Park Lamp/Side Marker Lamp is Always OFF

The headlamp switch is supplied with ground at all times. When the headlamp switch is placed in either the park or low beam position, ground is applied to the tail lamp signal circuit to the body control module (BCM). The BCM responds by applying battery voltage to the left/right park lamps, left/right side marker lamps and left/right tail lamps. This energizes the appropriate lamp.

  1. The engine is running.
  2. Headlamp switch in AUTO position.
  3. The ambient light is day.

B260B 01 or B260C 01

The BCM detects a short to voltage on the daytime running lamp relay control circuit.

B260B 02 or B260C 02

The BCM detects a short to ground on the daytime running lamp relay control circuit.

B260B 04 or B260C 04

The BCM detects an open/high resistance on the daytime running lamp relay control circuit.

The appropriate daytime running lamp will be continuously illuminated.

B260B 02, B260C 04, B260B 02 or B260C 04

The appropriate daytime running lamp will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Ignition ON, command the Left Dedicated Daytime Running Lamp and the Right Dedicated Daytime Running Lamp ON and OFF with a scan tool. The E4C daytime running lamp - left and the E4D daytime running lamp - right should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the appropriate KR42 daytime running lamp relay.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 86 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Connect a test lamp between the B+ circuit terminal 86 and the control circuit terminal 85.
  4. Command the appropriate Front Park Lamp test with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the KR42 daytime running lamp relay.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the appropriate KR42 daytime running lamp relay.
  2. Test for 60-180 ohms between terminals 85 and 86. If not within the specified range, replace the KR42 daytime running lamp relay.
  3. Test for infinite resistance between the following terminals: 30 and 86 30 and 87 30 and 85 85 and 87 If not the specified value, replace the KR42 daytime running lamp relay.
  4. Install a 15A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87. If greater than the specified range, replace the KR42 daytime running lamp relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Relay Replacement (Attached to Wire Harness)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Daytime Running Lamps ControlB260D 02B260D 04B260D 01
Right Daytime Running Lamps ControlB260E 02B260E 04B260E 01

When the headlight switch is in the Auto position and the ambient light sensor detects sunlight, the body control module (BCM) will command the daytime running lamps to illuminate by providing 12 volts to the daytime running lamp control circuit.

  1. The engine is running.
  2. Headlamp switch in AUTO position.
  3. The ambient light is day.

B260D 01 or B260E 01

The BCM detects a short to voltage on the daytime running lamp control circuit

B260D 02 or B260E 02

The BCM detects a short to ground on the daytime running lamp control circuit

B260D 04 or B260E 04

The BCM detects an open/high resistance on the daytime running lamp control circuit

The daytime running lamp will be continuously illuminated.

B260D 02, B260D 04, B260E 02 or B260E 04

The daytime running lamp will be inoperative

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Ignition ON, command the Left Dedicated Daytime Running Lamp and the Right Dedicated Daytime Running Lamp ON and OFF with a scan tool. The E4C daytime running lamp - left and the E4D daytime running lamp - right should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the X1 harness connector K9 BCM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 3 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the X1 harness connector K9 BCM
  4. Ignition OFF, disconnect the inline harness connector listed below: E4C daytime running lamp - left X111 inline harness connector E4D daytime running lamp - right X116 inline harness connector
  5. Connect a test lamp between the control circuit terminal G and ground.
  6. Command the appropriate Dedicated Daytime Running Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K9 BCM.
  7. If all circuits test normal, replace the daytime running lamp bulb.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Courtesy Lamps ControlB2615 0221
1. Courtesy Lamps Always Illuminated 2. Courtesy Lamps do Not Illuminate

Battery voltage for the courtesy lamps is supplied at all times to the body control module (BCM). When the BCM receives a signal to command the courtesy lamps ON, it then applies voltage through the courtesy lamps control circuits to the courtesy lamps.

The BCM attempts to illuminate the courtesy lamps.

The BCM detects a short to ground on the courtesy lamp control circuit.

The BCM will not attempt to activate courtesy lamps.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 100 consecutive malfunction ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Command the Courtesy Lamps ON and OFF with a scan tool. The courtesy lamps should turn ON and OFF when changing between commanded states.

  1. Disconnect the harness connector at the appropriate courtesy lamp.
  2. Ignition OFF, scan tool OFF, doors CLOSED, interior lamps OFF, test for less than 5.0 ohms between the ground circuit terminal listed below and ground: Instrument Panel Courtesy Lamp - terminal 2 Door Courtesy Lamp - terminal 2 Overhead Console Courtesy/Reading Lamp - terminal 2 Rear Courtesy/Reading Lamp - terminal B If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal listed below and ground: Instrument Panel Courtesy Lamp - terminal 1 Door Courtesy Lamp - terminal 1 Overhead Console Courtesy/Reading Lamp - terminal 3 Rear Courtesy/Reading Lamp - terminal C
  4. Command the Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the courtesy lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic repair.

  1. Refer to the appropriate replacement procedure for the lighting component that requires replacement.
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Switch B+B1405 03, B1529 03, B257B 03, 1B257B 03, 1
Instrument Panel Lamps Dimmer Switch SignalB257B 03, 1B257B 03, 1B257B 07
Interior Backlighting Control BCM Terminal 9 X7B2625 0221
Interior Backlighting Control BCM Terminal 8 X2B2625 02, 221
Interior Backlighting Control BCM Terminal 5 X1 (with UD5)B2625 0221
Headlamp Switch GroundB257B 03
1. Interior backlighting at full intensity and cannot be dimmed 2. Interior backlighting component does not illuminate

The dimmer switch is used to increase and decrease the brightness of the interior backlighting components. The body control module (BCM) supplies a reference voltage to the backlight dimmer switch, which is part of the headlamp switch. When the dimmer switch is placed in a desired brightness position, the dimmed voltage setting is applied through the dimmer switch and the dimmer switch signal circuit to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage through the backlight lamp control circuit and the LED dimming control circuit illuminating the components to the requested level.

The ignition is ON.

The BCM detects a short to ground in the LED dimming control circuit.

Actions Taken When the DTC Sets

The BCM will not attempt to illuminate the LED indicator lamps when a short circuit to ground is detected.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, park lamps ON, vary the interior backlight dimming from low to full bright by using the dimmer switch. The LED on all components should dim and then become full bright.

  1. Ignition OFF, disconnect the harness connector at any component on the interior backlighting control circuit.
  2. Scan tool disconnected, interior lamps OFF, doors CLOSED, test for less that 10 ohms between the ground circuit terminal and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal and ground.
  4. Ignition ON, command the LED Backlight Dimming ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the appropriate component.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. Refer to the appropriate replacement procedure for the component causing the condition.
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Ambient Light Sensor SignalB2645 03B2645 03B2645 07
Low ReferenceB0163 05, B0183 05, B1405 05, B2645 07

The ambient light sensor is used to monitor outside lighting conditions. The ambient light sensor provides a voltage signal that will vary between 1.4-4.5 V depending on outside lighting conditions. The body control module (BCM) monitors the ambient light sensor signal circuit to determine if outside lighting conditions are correct for either daytime running lights or automatic lamp control when the headlamp switch is in the AUTO position. In daylight conditions the BCM will command the daytime running lights ON. During low light conditions the BCM will command the low beam headlamps ON.

Ignition ON

B2645 03

The BCM detects a short to ground on the ambient light sensor signal circuit.

B2645 07

The BCM detects greater than 5 volts on the ambient light sensor signal circuit.

The automatic headlamps will malfunction.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Ignition ON, observe the scan tool Ambient Light Sensor parameter. The reading should be between 1.4-4.5 V and change with ambient light changes.

  1. Ignition OFF, disconnect the harness connector at the B10B ambient light/sunload sensor.
  2. Test for less than 30 ohms between the low reference circuit terminal 6 and ground. If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K33 HVAC control module.
  3. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 5 and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, replace the B10B ambient light/sunload sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Sun Load Temperature and Daytime Running Lamp Ambient Light Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM or HVAC control module replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Interior Accent Light ControlB2652 0221
1. Interior Accent Light at Full Intensity and Does Not Dim 2. Interior Accent Light do Not Illuminate

The body control module (BCM) uses the ambient light sensor to determine which brightness of the accent lighting is needed. The BCM applies a pulse width modulated (PWM) voltage through the accent light LED control circuit. Depending on the specified lighting requirements, the BCM has three different accent lighting settings

  1. Daylight conditions (70%)
  2. Night conditions (40%)
  3. Welcome light (100%)
  1. The ignition is ON.
  2. The headlamps or park lamps ON.

The BCM detects a short to ground on the accent lighting control circuit.

The BCM does not attempt to illuminate the accent lighting.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 100 consecutive malfunction ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the Accent Lighting ON and OFF with a scan tool. The accent lighting should turn ON and OFF when changing between the commanded states.

  1. Ignition OFF, disconnect the harness connectors at the appropriate E1 accent light.
  2. Test for less than 5 ohms between the ground circuit terminal and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition OFF, doors closed, wait 20 seconds before testing for less than 0.3 V between the control circuit terminal and ground. If greater than the specified value, test the circuit for a short to voltage. If the circuits test normal replace the K9 BCM.
  4. Ignition ON, doors open, test for greater than 11 V between the control circuit terminal and ground. If less than the specified value, test the circuit for a short to ground or an open/high resistance. If the circuits test normal replace the K9 BCM.
  5. If all circuits test normal, test or replace the E1 accent light.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. Refer to the appropriate replacement procedure for the lighting component that requires replacement.
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Ignition Switch Halo Lamp ControlB2657 0221
Ignition Switch Halo Lamp Ground2
1. Ignition Switch Halo Lamp Always ON 2. Ignition Switch Halo Lamp Always OFF

The body control module (BCM) supplies a voltage reference through the backlight dimmer switch, which is part of the headlamp switch. When the dimmer switch is placed in a desired brightness position, reference voltage is applied through the backlight dimmer switch to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage through the backlight lamp control circuit. This will illuminate the ignition mode switch halo lamp.

  1. The ignition is ON.
  2. The headlamps or park lamps are ON.

The BCM detects a short to ground on the ignition switch halo lamp control circuit.

The BCM will not illuminate the ignition switch halo lamp.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 100 consecutive malfunction ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the LED Backlighting ON and OFF with a scan tool. The ignition switch halo lamp should turn ON and OFF when changing between the commanded states.

  1. Ignition OFF, disconnect the harness connector at the S38 ignition mode switch.
  2. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 10 ohms between the ground circuit terminal 4 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal 8 and the ground circuit terminal 4.
  4. Command the LED Backlighting ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the S38 ignition mode switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Ignition and Start Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Lighting Control Switch ReferenceB1405 03, B1529 03, B2740 00B257B 031
Lighting Control Switch SignalB257B 03B257B 031
1. Front Fog Switch Malfunction

The front fog lamp relay is supplied with battery voltage at all times. The front fog lamp switch signal circuit is grounded momentarily by pressing the front fog lamp switch. The body control module (BCM) energizes the front fog lamp relay by applying ground to the front fog lamp relay control circuit. When the front fog lamp relay is energized, the relay switch contacts close and battery voltage is applied through the front fog lamp fuse to the front fog lamp supply voltage circuit which illuminates the front fog lamps.

  1. The ignition is turned ON.
  2. Front fog lamp switch activated.

The BCM detects the fog lamp switch is continuously active.

Front fog lamps will be continuously illuminated.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

The condition for setting the DTC is not longer present.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool Front Fog Lamps Switch parameter while turning the front fog lamps switch ON and OFF. The parameter should change between Active and Inactive.

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Ignition ON, test for greater than 10V between the 12 V reference circuit terminal 1 and ground. If less than the specified range, test the 12 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  3. Test for 0.4K ohms to 1K ohms between the signal circuit terminal 12 and ground. If greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If less than the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, test or replace the S30 headlamp switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Leveling Sensor 5V Reference - FrontB3415 021B3415 01
Headlamp Leveling Sensor 5V Reference - RearB3415 021B3415 01
Headlamp Leveling Sensor Signal - FrontB3410 06B3410 06B3410 01
Headlamp Leveling Sensor Signal - RearB3420 06B3420 06B3420 01
Headlamp Leveling Sensor Low Reference - FrontB3410 06
Headlamp Leveling Sensor Low Reference - Rear1
1. Headlamp Leveling Malfunction

The front and rear suspension position sensors provide the headlamp control module with front and rear suspension position information. Each sensor receives a 5V reference, signal, and low reference circuits from the headlamp control module. The sensors are connected to the control arms at the front and rear suspension. As the vehicle travels, the suspension compresses and rebounds moving the suspension position sensor arms. This causes the signal output of the sensors to change. The headlamp control module compares the information from the front and rear suspension position sensors and adjusts the headlamp leveling as needed.

  1. Battery voltage must be between 9-16 V.
  2. The ignition is in the ON or RUN position.
  3. The headlamps are ON.

B3410 01 or B3420 01

The headlamp leveling control module detects a short to battery on the sensor signal line.

B3410 06 or B3420 06

The headlamp leveling control module detects a short to ground or an open/high resistance on the sensor signal line.

  1. The headlamp control module disables the headlamp leveling system.
  2. The driver information center will display Service AFL Lamp message.
  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition OFF, disconnect the harness connector at the appropriate B51 headlamp leveling sensor.
  2. Test for less than 5 ohms between the low reference circuit terminal 3 and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  3. Ignition ON, test for 4.8-5.2 V between the 5V reference circuit terminal 1 and ground. If less than the specified range, test the 5V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module. If greater than the specified range, test the 5V reference circuit for a short to voltage. If the circuit tests normal, replace the K28 headlamp leveling control module.
  4. Verify the appropriate scan tool Leveling Position Sensor parameter is 0 V. If greater than the specified range, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the K28 headlamp leveling control module.
  5. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the 5V reference circuit terminal 1. Verify the appropriate scan tool Leveling Position Sensor parameter is greater than 5 V. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  6. If all circuits test normal, replace the B51 headlamp leveling sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Leveling Front Suspension Height Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Leveling Rear Suspension Height Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for headlamp leveling control module replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Leveling Sensor 5V Reference - FrontB3415 021B3415 01
Headlamp Leveling Sensor 5V Reference - RearB3415 021B3415 01
Headlamp Leveling Sensor Signal - FrontB3410 06B3410 06B3410 01
Headlamp Leveling Sensor Signal - RearB3420 06B3420 06B3420 01
Headlamp Leveling Sensor Low Reference - Front1
Headlamp Leveling Sensor Low Reference - Rear1
1. Headlamp Leveling Malfunction

The front and rear suspension position sensors provide the headlamp control module with front and rear suspension position information. Each sensor receives a 5V reference, signal, and low reference circuits from the headlamp control module. The sensors are connected to the control arms at the front and rear suspension. As the vehicle travels, the suspension compresses and rebounds moving the suspension position sensor arms. This causes the signal output of the sensors to change. The headlamp control module compares the information from the front and rear suspension position sensors and adjusts the headlamp leveling as needed.

  1. Battery voltage must be between 9-16 V.
  2. The ignition is in the ON or RUN position.
  3. The headlamps are ON.

B3415 01

The headlamp leveling control module detects a short to voltage on the sensor signal line.

B3415 02

The headlamp leveling control module detects a short to ground or an open/high resistance on the sensor signal line.

  1. The headlamp control module disables the headlamp leveling system.
  2. The driver information center will display Service AFL Lamp message.
  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition OFF, disconnect the harness connector at the appropriate B51 headlamp leveling sensor.
  2. Test for less than 5 ohms between the low reference circuit terminal 3 and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  3. Ignition ON, test for 4.8-5.2 V between the 5V reference circuit terminal 1 and ground. If less than the specified range, test the 5V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module. If greater than the specified range, test the 5V reference circuit for a short to voltage. If the circuit tests normal, replace the K28 headlamp leveling control module.
  4. Verify the appropriate scan tool Leveling Position Sensor parameter is 0 V. If greater than the specified range, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the K28 headlamp leveling control module.
  5. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the 5V reference circuit terminal 1. Verify the appropriate scan tool Leveling Position Sensor parameter is greater than 5 V. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  6. If all circuits test normal, replace the B51 headlamp leveling sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Leveling Front Suspension Height Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Leveling Rear Suspension Height Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for headlamp leveling control module replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Switch Reference VoltageB257B 03B257B 03B3588 00
Headlamp Switch SignalB257B 03B257B 03B257B 07

The body control module (BCM) supplies a reference voltage to the backlight dimmer switch, which is part of the headlamp switch. When the backlight dimmer switch is placed in a desired brightness position, reference voltage is applied through the backlight dimmer switch resistor ladder to the BCM. The BCM interprets this voltage signal and will command the interior lights to the desired brightness, command the front fog lamps or the rear fog lamps depending upon the switch setting selected.

  1. The ignition is turned ON.
  2. Low beam or front fog lamps illuminated.
  3. Rear fog lamp switch activated.

Rear fog lamp switch stuck.

  1. All cluster/backlighting defaults full bright
  2. Steering wheel cluster/backlighting dimming controls inoperative
  3. Front fog lamps are inoperative
  4. Rear fog lamps are inoperative
  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 40 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool Rear Fog Lamps Switch parameter. The parameter should change between Active and Inactive each time the rear fog lamp switch is pressed.

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Ignition OFF, test for 0.4k ohms to 1 ohms between the signal circuit terminal 12 and ground. If greater than the specified value, test the low reference circuit for an short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If less than the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the K9 BCM.
  3. Test for greater than 10 V between the 12 V reference circuit terminal 1 and ground. If less than the specified range, test the 12 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, replace the K9 BCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Hazard Lamps Request SignalB3596 0011
1. Hazard Function Inoperative

When the hazard switch is placed in the ON position, ground is momentarily applied through the hazard switch signal circuit to the body control module (BCM). The BCM will detect this voltage drop and will supply battery voltage to all four turn signal lamps in an ON and OFF duty cycle. When the hazard switch is activated, the BCM sends a serial data message to the instrument panel cluster (IPC) requesting both turn signal indicators to be cycled ON and OFF.

Ignition is ON

The BCM detects a short to ground on the hazard switch signal circuit for greater than 1 min

The hazard lamps will continuously function.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Observe the function of the right and left turn signal lamps while turning the hazard lamp switch ON and OFF. The right and left turn signal lamps should cycle ON and OFF while the hazard lamp switch is ON and remain OFF when the hazard lamp switch is OFF.

  1. Ignition OFF, disconnect the harness connector at the P17 info display module.
  2. Ignition ON, test for greater than 10V between the signal circuit terminal 16 and ground. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  3. If all circuits test normal, replace the P17 info display module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Radio Control Assembly Replacement»(/cadillac/srx/ii-2009-2012/remont/entertainment-systems/#cellular-systems-entertainment-systems-navigation-systems)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Front Fog Lamps Switch SignalB2740 00

The front fog lamp relay is supplied with battery voltage at all times. The front fog lamp switch signal circuit is grounded momentarily by pressing the front fog lamp switch. The body control module (BCM) energizes the front fog lamp relay by applying ground to the front fog lamp relay control circuit. When the front fog lamp relay is energized, the relay switch contacts close and battery voltage is applied through the front fog lamp fuse to the front fog lamp supply voltage circuit which illuminates the front fog lamps.

  1. The ignition is turned ON.
  2. Front fog lamp switch activated.

Front fog lamps malfunction

Front fog lamp switch stuck

The condition for setting the DTC is not longer present.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool Front Fog Lamps Switch parameter. The reading should change between Active/Inactive when changing between pressed and released front fog lamp switch button.

  1. Ignition OFF, disconnect the X1 and X3 harness connector at the K9 Body Control Module.
  2. Ignition ON, test for less than 0.3 V at the K9 Body Control Module signal circuit harness terminal 9 X1 and ground. If greater then the specified value, test the signal circuit for an short to voltage.
  3. Test for less than 0.3 V at the K9 Body Control Module 12 V reference circuit harness terminal 4 X3 and ground. If greater than the specified value, test the 12 V reference circuit for a short to voltage.
  4. Ignition OFF, test for infinite resistance between the K9 Body Control Module signal circuit harness terminal 9 X1 and ground. If lower than the specified value, test the signal circuit for a short to ground.
  5. Test for infinite resistance between the K9 Body Control Module 12 V reference circuit harness terminal 4 X3 and ground. If lower than the specified value, test the 12 V reference circuit for a short to ground.
  6. Press and hold the front fog lamp switch button.
  7. Test for 2.6-3.2 kohms between the K9 Body Control Module 12 V reference circuit harness connector X3 terminal 4 and the K9 Body Control Module signal circuit harness terminal 9 X1. If not within the specified range, test the 12 V reference circuit and the signal circuit for an open/high resistance. If the circuits test normal, replace the S30 Headlamp Switch.
  8. If all circuits test normal, replace the K9 Body Control Module.

Static Test

Ignition OFF, disconnect the harness connector at the S30 Headlamp Switch. Press and hold the front fog lamp switch button, test for 2.6-3.2 kohms at the S30 Headlamp Switch terminal 1 and terminal 12.

  1. If not within the specified range replace the S30 Headlamp Switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp High Beam SignalB3650 0811
Headlamp Flash To Pass SignalB3806 0022
Turn Signal/Multifunction Switch Ground1, 2
1. Headlamp Dimmer Switch Malfunction 2. Headlamp Flash To Pass Switch Malfunction

The BCM monitors the voltage level within the high beam signal circuit and the flash to pass signal circuit. When the turn signal/multifunction switch is moved to the high beam position or to the flash to pass position, the voltage within the appropriate signal circuit drops to less than 1 V. The BCM will detect the voltage drop and will command the headlamp high beams to turn ON or OFF.

Battery voltage must be between 9-16 V.

The BCM detects a short to ground in the headlamp high beam signal circuit.

The high beam headlamps will malfunction.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool High Beam Select Switch parameter while pulling and releasing the turn signal/multi-function switch. The value should change between Inactive and Active when changing between the selected states.

  1. Ignition OFF, disconnect at the S78 turn signal/multifunction switch.
  2. Ignition ON, verify that the scan tool High Beam Select Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  3. Connect a 3 A fused jumper wire between the signal circuit terminal 2 and ground, verify that the scan tool High Beam Select Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, test or replace the S78 turn signal/multifunction switch.

Turn Signal/Multifunction Switch Test

  1. Ignition OFF, disconnect the harness connector at the S78 turn signal/multifunction switch.
  2. Test for Infinite resistance between the terminals listed below with the switch in the open position. Signal terminal 2 and ground terminal 3 Signal terminal 4 and ground terminal 3 If not the specified value, replace the S78 turn signal/multifunction switch.
  3. Test for less than 2 ohms between the signal terminal 2 and the ground terminal 3 with the switch in the high beam position. If greater than the specified value, replace the S78 turn signal/multifunction switch.
  4. Test for less than 2 ohms between the signal terminal 4 and the ground terminal 3 while holding the switch in the flash to pass position. If greater than the specified value, replace the S78 turn signal/multifunction switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Turn Signal Multifunction Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/steering-column-switches/#steering-wheel-and-steering-column)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp High Beam SignalB3650 0811
Headlamp Flash To Pass SignalB3806 0022
Turn Signal/Multifunction Switch Ground1, 2
1. Headlamp Dimmer Switch Malfunction 2. Headlamp Flash To Pass Switch Malfunction

The BCM monitors the voltage level within the high beam signal circuit and the flash to pass signal circuit. When the turn signal/multifunction switch is moved to the high beam position or to the flash to pass position, the voltage within the appropriate signal circuit drops to less than 1 V. The BCM will detect the voltage drop and will command the headlamp high beams to turn ON or OFF.

Battery voltage must be between 9-16 V.

The BCM detects a short to ground in the headlamp flash to pass signal circuit for greater than 15 seconds.

The high beam headlamps will malfunction.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool Headlamps Flash Switch parameter while pulling and releasing the turn signal/multifunction switch. The value should change between Inactive and Active when changing between the selected states.

  1. Ignition OFF, disconnect at the S78 turn signal/multifunction switch.
  2. Ignition ON, verify that the scan tool Headlamps Flash Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  3. Connect a 3 A fused jumper wire between the signal circuit terminal 4 and ground, verify that the scan tool Headlamps Flash Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, test or replace the S78 turn signal/multifunction switch.
  1. Ignition OFF, disconnect the harness connector at the S78 turn signal/multifunction switch.
  2. Test for Infinite resistance between the terminals listed below with the switch in the open position. Signal terminal 2 and ground terminal 3 Signal terminal 4 and ground terminal 3 If not the specified value, replace the S78 turn signal/multifunction switch.
  3. Test for less than 2 ohms between the signal terminal 2 and the ground terminal 3 with the switch in the high beam position. If greater than the specified value, replace the S78 turn signal/multifunction switch.
  4. Test for less than 2 ohms between the signal terminal 4 and the ground terminal 3 while holding the switch in the flash to pass position. If greater than the specified value, replace the S78 turn signal/multifunction switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Turn Signal Multifunction Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/steering-column-switches/#steering-wheel-and-steering-column)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Stop Lamp ControlB3881 02B3881 041
Right top Lamp ControlB3882 02B3882 041
1. Stop Lamps Always ON

The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an analog voltage signal to the body control module (BCM). The BCM will apply battery voltage to the right, left and center stop lamp control circuits.

Brake pedal is applied.

B3881 01

The BCM detects a short to voltage on the left rear brake lamp control circuit.

B3881 02

The BCM detects a short to ground on the left rear brake lamp control circuit.

B3882 01

The BCM detects a short to voltage on the right rear brake lamp control circuit.

B3882 02

The BCM detects a short to ground on the right rear brake lamp control circuit.

The appropriate brake lamp will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the function of the E5L stop lamp-left while commanding the Left Brake Lamp ON and OFF with a scan tool. The E5L stop lamp-left should turn ON and OFF while changing between the commanded states
  2. Observe the function of the E5R stop lamp-right while commanding the Right Brake Lamp ON and OFF with a scan tool. The E5R stop lamp-right should turn ON and OFF while changing between the commanded states.
  1. Ignition OFF, disconnect the X1 harness connector at the appropriate E5 tail lamp.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance
  3. Connect a test lamp between the control circuit terminal A and ground
  4. Ignition ON, command the Brake Lamp ON and OFF with a scan tool, the test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the E5 tail lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Tail Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
License Plate Lamp ControlB3883 02B3883 041
1. License Plate Lamps Always ON

The headlamp switch is supplied with ground at all times. When the headlamp switch is placed in either the park or low beam position, the BCM responds by applying battery voltage to the license plate lamp control circuit. This energizes the left and right license lamp.

Headlamp switch in park or low beam position.

B3883 02

The BCM detects a short to ground on the license plate lamp control circuit.

B3883 04

The BCM detects an open/high resistance on the license plate lamp control circuit.

The license plate lamps will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the License Plate Lamps ON and OFF with a scan tool. The license plate lamps should turn ON and OFF when changing between the commanded states.

  1. Ignition OFF, disconnect the X902 inline harness connector.
  2. Test for less than 10 ohms between the ground circuit terminal 15 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal 1 and ground.
  4. Ignition ON, command the license plate lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the selected states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the E7L license plate lamp-left or E7R license plate lamp-right.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Liftgate Center Applique Replacement»(/cadillac/srx/ii-2009-2012/remont/exteriorinterior-trim/#exterior-trim)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Center High Mounted Brake Lamp ControlB3884 02B3884 041B0655 5A
Center High Mounted Brake Lamp GroundB3884 04
1. Center High Mounted Brake Lamp Always ON

The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an analog voltage signal to the body control module (BCM). The BCM will apply battery voltage to the right, left and center stop lamp control circuits.

The brakes are applied.

B3884 02

The BCM detects a short to ground on the center high mounted brake lamp control circuit

B3884 04

The BCM detects an open/high resistance on the center high mounted brake lamp control circuit

The center high mounted brake lamp will not illuminate.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the E6 center high mounted stop lamp ON and OFF by applying and releasing the brake pedal. The E6 center high mounted stop lamp should turn ON and OFF each time the brake pedal is applied and released.

  1. Ignition OFF, disconnect the harness connector at the E6 center high mounted stop lamp.
  2. Test for less than 30 ohms between the ground circuit terminal B and ground. If greater than the specified value, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal A and ground.
  4. Ignition ON, command the center high mounted stop lamp ON and OFF by applying and releasing the brake pedal. The test lamp should turn ON and OFF when changing between the selected states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the E6 center high mounted stop lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «High Mount Stop Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Trailer Left Tail Lamp ControlB3885 02B3885 04
Trailer Right Tail Lamp ControlB3886 02B3886 04

The trailer brake control module will receive a serial data message from the body control module (BCM) indicating that the vehicle park lamps have been activated. The trailer brake control module will then apply system voltage to the trailer tail lamps through their respective voltage supply circuits.

When the parking lamps are turned on.

B3885 02 or B3886 02

The trailer brake control module detects a short to ground on the appropriate tail lamp control circuit.

B3885 04 or B3886 04

The trailer brake control module detects an open/high resistance in the appropriate tail lamp control circuit.

The appropriate trailer tail lamp will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 40 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the left trailer tail lamp and the right trailer tail lamp while commanding the Left Trailer Tail Lamp and the Right Trailer Tail Lamp ON and OFF with a scan tool. The left trailer tail lamp and the right trailer tail lamp should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the X1 harness connector at the K68 trailer lighting control module.
  2. Test for infinite resistance between the control circuit terminal listed below and ground: Right trailer park lamp control terminal 16 Left trailer park lamp control terminal 4 If less than the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X88 trailer connector.
  3. Test for less than 1 ohms between the control circuit terminals listed below: Control terminal 16 at the K68 trailer lighting control module and control terminal 5 at the X88 trailer connector. Control terminal 4 at the K68 trailer lighting control module and control terminal 7 at the X88 trailer connector. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the X88 trailer connector.
  4. If all the circuits test normal, replace the K68 trailer lighting control module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for trailer brake control module replacement, programming and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Trailer Left Turn SignalB3887 02B3887 041
Trailer Right Turn SignalB3888 02B3888 042
1. Left Trailer Turn Signal Lamp Always On 2. Right Trailer Turn Signal Lamp Always On

The trailer brake control module will receive a serial data message from the BCM indicating that the vehicle left turn signal lamp or the right turn signal lamp has been activated. The trailer brake control module will then apply a pulsating voltage to the appropriate trailer turn signal lamps through their respective voltage supply circuits.

When the trailer left turn lamp or right turn lamp is being actively commanded by the trailer brake control module.

B3887 02 or B3888 02

The trailer brake control module detects a short to ground on the appropriate turn signal control circuit.

B3887 04 or B3888 04

The trailer brake control module detects an open/high resistance in the appropriate turn signal control circuit.

The appropriate trailer turn signal lamp will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 40 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the left trailer turn signal lamp and the right trailer turn signal lamp while commanding the Left Trailer Turn Signal Lamp and the Right Trailer Turn Signal Lamp ON and OFF with a scan tool. The left trailer turn signal lamp and the right trailer turn signal lamp should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the X1 harness connector at the K68 trailer lighting control module.
  2. Test for infinite resistance between the control circuit terminal listed below and ground: Right trailer turn signal lamp control terminal 2 Left trailer turn signal lamp control terminal 17 If less than the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X88 trailer connector.
  3. Test for less than 1 ohms between the control circuit terminals listed below: Control terminal 2 at the K68 trailer lighting control module and control terminal 4 at the X88 trailer connector. Control terminal 17 at the K68 trailer lighting control module and control terminal 1 at the X88 trailer connector. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance.
  4. If all the circuits test normal, replace the K68 trailer lighting control module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for trailer brake control module replacement, programming and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Trailer Turn Signal Lamp ControlB3887 02B3887 041
Right Trailer Turn Signal Lamp ControlB3888 02B3888 042
1. Left Trailer Turn Signal Lamp Inoperative 2. Right Trailer Turn Signal Lamp Inoperative

When the appropriate turn signals are activated, the BCM will apply a pulsating ground to the appropriate trailer stop/turn signal lamp relay.

The system voltage is 9-16 V.

The BCM detects a short to ground on the appropriate trailer turn signal control circuit.

The BCM detects an open/high resistance on the appropriate trailer turn signal control circuit

The appropriate trailer turn signal lamp will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 40 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the left trailer turn signal lamp and the right trailer turn signal lamp while commanding the Left Trailer Turn Signal Lamp and the Right Trailer Turn Signal Lamp ON and OFF with a scan tool. The left trailer turn signal lamp and the right trailer turn signal lamp should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the X5 harness connector at the K9 BCM.
  2. Ignition ON, test for greater than 10 V between the control circuit terminal listed below and ground: Right trailer turn signal lamp control terminal 17 Left trailer turn signal lamp control terminal 8 If less than the specified value, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50 A fuse block-underhood.
  3. If all the circuits test normal, replace the K9 BCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Fuse Block Replacement»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Trailer Stop Lamps ControlB3889 02B3889 041
1. Trailer Stop Lamps Always ON

The trailer brake control module will receive a serial data message from the BCM indicating that the vehicle brake lamps have been activated. The trailer brake control module will then apply system voltage to the trailer stop lamps through their respective voltage supply circuits.

When the brake pedal is pressed.

B3889 02

The trailer brake control module detects a short to ground on the trailer stop lamp control circuit.

B3889 04

The trailer brake control module detects an open/high resistance on the trailer stop lamp control circuit.

The trailer brake lamps will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 40 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the trailer stop lamps while commanding the Trailer Stop Lamp ON and OFF with a scan tool. The trailer stop lamps should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the X1 harness connector at the K68 trailer lighting control module.
  2. Test for infinite resistance between the control circuit terminal 10 and ground. If less than the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X88 trailer connector.
  3. Test for less than 1 ohms between the control circuit terminal 10 at the K68 trailer lighting control module and control circuit terminal 6 at the X88 trailer connector. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the X88 trailer connector.
  4. If all the circuits test normal, replace the K68 trailer lighting control module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for trailer brake control module replacement, programming and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Trailer Park Lamp Relay B+B388A 04B388A 04
Park Lamp Supply Voltage/Marker Lamp Supply VoltageB388A 02B388A 04B388A 01

The trailer park lamp relay is supplied with battery voltage at all times. The trailer park lamp signal circuit is grounded by turning the headlamp switch. The body control module (BCM) energizes the trailer park lamp relay by applying ground to the trailer park lamp relay control circuit. When the trailer park lamp relay is energized, the relay switch contacts close and battery voltage is applied through the trailer park lamp relay fuse to the trailer park lamp supply voltage circuit which illuminates the trailer park lamps if a trailer is connected.

When the trailer park lamp relay is actively being requested by the BCM.

B388A 01

The BCM detects a short to voltage on the park lamp supply voltage/marker lamp supply voltage circuit.

B388A 02

The BCM detects a short to ground on the park lamp supply voltage/marker lamp supply voltage circuit

B388A 04

The BCM detects an open/high resistance on the park lamp supply voltage/marker lamp supply voltage circuit

B388A 01 or B388A 04

The trailer park lamps are inoperative

The trailer park lamps are always ON

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 40 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the trailer tail lamps while commanding the Trailer Park Lamps ON and OFF with a scan tool. The trailer tail lamps should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the trailer park lamp relay.
  2. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 86 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Connect a test lamp between the control circuit terminal 85 and the B+ circuit terminal 86.
  4. Command the Trailer Park Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM
  5. If all circuits test normal, test or replace the trailer park lamp relay.
  1. Ignition OFF, disconnect the trailer park lamp relay.
  2. Test for 60-180 ohms between terminals 85 and 86. If not within the specified range, replace the trailer park lamp relay.
  3. Test for infinite resistance between the following terminals: 30 and 86 30 and 87 30 and 85 85 and 87 If not the specified value, replace the trailer park lamp relay.
  4. Install a 5 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87. If greater than the specified range, replace the trailer park lamp relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Relay Replacement (Attached to Wire Harness)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Trailer Backup Lamps ControlB3890 02B3890 041
1. Trailer Backup Lamps Always ON

The trailer brake control module will receive a serial data message from the BCM indicating that the vehicle backup lamps have been activated. The trailer brake control module will then apply system voltage to the trailer backup lamps through their respective voltage supply circuits.

When the trailer backup lamps are turned on.

B3890 02

The trailer brake control module detects a short to ground on the trailer backup lamp control circuit.

B3890 04

The trailer brake control module detects an open/high resistance on the trailer backup lamp control circuit.

The trailer backup lamps will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 40 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the trailer backup lamps while commanding the Trailer Backup Lamp ON and OFF with a scan tool. The trailer backup lamps should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the X1 harness connector at the K68 trailer lighting control module.
  2. Test for infinite resistance between the control circuit terminal 7 and ground. If less than the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X88 trailer connector.
  3. Test for less than 1 ohms between the control circuit terminal 7 at the K68 trailer lighting control module and control circuit terminal 8 at the X88 trailer connector. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the X88 trailer connector.
  4. If all the circuits test normal, replace the K68 trailer lighting control module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for the trailer brake control module replacement, setup and programming

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Trailer Fog Lamps ControlB3891 02B3891 041
1. Trailer Fog Lamps Always ON

The trailer brake control module will receive a serial data message from the BCM indicating that the vehicle rear fog lamps have been activated. The trailer brake control module will then apply system voltage to the trailer fog lamps through their respective voltage supply circuits.

When the trailer fog lamps are turned on.

B3891 02

The trailer brake control module detects a short to ground on the trailer fog lamp control circuit.

B3891 04

The trailer brake control module detects an open/high resistance on the trailer fog lamp control circuit.

The trailer fog lamps will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 40 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the function of the trailer fog lamps while commanding the Trailer Fog Lamp ON and OFF with a scan tool. The trailer fog lamps should turn ON and OFF while changing between the commanded states.

  1. Ignition OFF, disconnect the X1 harness connector at the K68 trailer lighting control module.
  2. Test for infinite resistance between the control circuit terminal 8 and ground. If less than the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X88 trailer connector.
  3. Test for less than 1 ohms between the control circuit terminal 8 at the K68 trailer lighting control module and control circuit terminal 2 at the X88 trailer connector. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the X88 trailer connector.
  4. If all the circuits test normal, replace the K68 trailer lighting control module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for the trailer brake control module replacement, programming and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Front Turn Signal Lamp ControlB3948 0212
Right Front Turn Signal Lamp ControlB3949 0212
Left Repeater Lamp ControlB3948 0212
Right Repeater Lamp ControlB3949 0212
Left Tail Lamp Ground1
Right Tail Lamp Ground1
1. Turn Signal Lamps Inoperative 2. Turn Signal Lamps Always ON

Ground is applied at all times to the turn signal/multifunction switch. The turn signal lamps may only be activated with the ignition switch in the ON or START position. When the turn signal/multifunction switch is placed in either the TURN RIGHT or TURN LEFT position, ground is applied to the body control module through either the right turn or left turn signal switch signal circuit. The BCM then applies a pulsating voltage to the front and rear turn signal lamps through there respective voltage supply circuits. When a turn signal request is received by the BCM, a serial data message is sent to the instrument cluster requesting the respective turn signal indicator be pulsed ON and OFF.

When the appropriate turn signal is commanded

B3948 02

The BCM detects a short to ground on the left front turn signal control circuit.

B3949 02

The BCM detects a short to ground on the right front turn signal control circuit.

The appropriate turn signal lamp is inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, with the turn signal switch in the left position, observe the function of the E4LF turn signal lamp-left front and the E4Y turn signal repeater lamp-left. Each lamp should flash ON and OFF.
  2. With the turn signal switch in the right position, observe the function of the E4RF turn signal lamp-right front and the E4Z turn signal repeater lamp-right. Each lamp should flash ON and OFF.
  1. Ignition OFF, disconnect the harness connector at the appropriate turn signal lamp.
  2. Test for less than 30 ohms between the ground circuit terminal listed below and ground. E4Y turn signal repeater lamp-left terminal 2 E4Z turn signal repeater lamp-right terminal 2 If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Disconnect the inline harness connector at the appropriate E4LF turn signal lamp-front listed below: E4LF turn signal lamp-left front X115 (Without TT6/TT7/TT8) E4LF turn signal lamp-left front X111 (With TT6/TT7/TT8) E4RF turn signal lamp-right front X116 (Without TT6/TT7/TT8) E4RF turn signal lamp-right front X112 (With TT6/TT7/TT8)
  4. Connect a test lamp between the control circuit terminal listed below and ground. E4LF turn signal lamp-left front terminal J E4RF turn signal lamp-right front terminal J E4Y turn signal repeater lamp-left terminal 1 E4Z turn signal repeater lamp-right terminal 1
  5. Command the appropriate Turn Signal Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. If all circuits test normal, replace the turn signal lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Front Side Turn Signal Lamp Bulb Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Front Turn Signal Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Front Turn Signal Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__front-turn-signal-lamp-bulb-replacement) or «Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
BCM B+B2545 01, B2545 04, B3950 01, B3950 04B2545 01, B2545 04, B3950 01, B3950 04
Left Rear Turn Signal Lamp Supply VoltageB3950 0221
Right Rear Turn Signal Lamp Supply VoltageB3951 0221
1. Rear Turn Signal Lamp Always ON 2. Rear Turn Signal Lamp Always OFF

Ground is applied at all times to the turn signal/multifunction switch. The turn signal lamps may only be activated with the ignition switch in the ON or START position. When the turn signal/multifunction switch is placed in either the TURN RIGHT or TURN LEFT position, ground is applied to the body control module through either the right turn or left turn signal switch signal circuit. The BCM then applies a pulsating voltage to the front and rear turn signal lamps through there respective voltage supply circuits. When a turn signal request is received by the BCM, a serial data message is sent to the instrument cluster requesting the respective turn signal indicator be pulsed ON and OFF.

The appropriate turn signal is active

The BCM detects a short to ground on the rear turn signal control circuit

The appropriate rear turn signal will be inoperative.

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

  1. Ignition ON, command the Left Rear Turn Signal Lamp ON and OFF with a scan tool. The left rear turn signal lamp should turn ON and OFF when changing between the commanded states.
  2. Command the Right Rear Turn Signal Lamp ON and OFF with a scan tool. The right rear turn signal lamp should turn ON and OFF when changing between the commanded states.
  1. Ignition OFF, disconnect the X2 harness connector K9 BCM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance
  3. Ignition OFF, connect the X2 harness connector K9 BCM.
  4. Ignition OFF, disconnect the X2 harness connector at the appropriate E4 turn signal lamp-rear.
  5. Test for less than 30 ohms between the ground circuit terminal 1 and ground. If greater than the specified value, test the ground circuit for an open/high resistance.
  6. Connect a test lamp between the control circuit terminal 3 and ground.
  7. Command the appropriate Rear Turn Signal Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  8. If all the circuits test normal, replace the bulb or E4 turn signal lamp-rear.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Rear Turn Signal Lamp Bulb Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
5 V ReferenceC0277 06, C0890 03C0277 06C0277 07, C0890 07
SignalC0277 06, C0890 03C0277 06C0277 07, C0890 07C0277 09
Low ReferenceC0277 07

The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an analog voltage signal that will increase as the brake pedal is applied. The body control module provides a low reference signal and a 5 V reference voltage to the brake pedal position sensor. When the variable signal reaches a voltage threshold indicating the brakes have been applied, the BCM will apply battery voltage to the stop lamp control circuit and center high mounted stop lamp control circuit. When the control circuit is energized the stop lamps are illuminated.

  1. Battery voltage must be between 9-16 V
  2. Brakes applied

C0277 06 or C0890 03

  1. The BCM detects a short to ground or an open/high resistance in the brake pedal position sensor signal circuit.
  2. The BCM detects a short to ground or an open/high resistance in the brake pedal position sensor 5 V reference circuit.

C0277 07 or C0890 07

  1. The BCM detects a short to battery voltage in the brake pedal position sensor signal circuit.
  2. The BCM detects an open/high resistance in the brake pedal position sensor low reference circuit.

C0277 09

The BCM detects the brake pedal position sensor signal is changing faster than possible under normal operating conditions.

C0277 4B

The brake pedal position sensor home position is not learned.

Brake lights will malfunction, the shift lock is inoperative, the service park brake system lamp illuminated in IPC, park brake will set but not disengage

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

If the DTC is set, recalibrate the brake pedal position sensor.

If the DTC is set, replace the brake pedal position sensor. If the DTC resets, replace the BCM.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

C0277 06, C0277 07, C0890 03, C0890 07

  1. Ignition OFF, disconnect the harness connector at the B22 brake pedal position sensor.
  2. Ignition OFF, test for less than 60 ohms between the low reference circuit terminal C and ground. If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  3. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal A and ground. If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  4. Verify that the scan tool Brake Pedal Position Sensor parameter is less than 0.3 V. If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. Connect a 3 A fused jumper wire between the 5 V reference circuit terminal A and the signal circuit terminal B. Verify that the scan tool Brake Pedal Position Sensor parameter is 4.8-5.2 V If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. If all circuits test normal, test or replace the B22 brake pedal position sensor.
  1. Replace the B22 BPP sensor.
  2. Perform the BPP sensor recalibration procedure. Refer to «Brake Pedal Position Sensor Calibration»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__brake-pedal-position-sensor-calibration) .
  3. Operate the vehicle within the Conditions for Running and Setting the DTC and verify the DTC does not reset. If the DTC resets, replace the K9 BCM.
  1. Verify that the DTC sets under the Conditions for Running and Setting.
  2. Perform the BPP sensor recalibration procedure. Refer to «Brake Pedal Position Sensor Calibration»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__brake-pedal-position-sensor-calibration) .
  3. Operate the vehicle within the conditions that the customer experienced and verify the DTC does not reset. If the DTC resets, replace the B22 BPP sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Brake Pedal Position Sensor Calibration»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__brake-pedal-position-sensor-calibration)
  2. «Brake Pedal Position Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__brake-pedal-position-sensor-replacement)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Cruise/ETC/TCC Brake SignalC0297 02, P0572P0572P0573

The stop lamp switch signal circuit is a B+ input from the body control module (BCM) to the engine control module (ECM). The ECM monitors the stop lamp switch circuit to detect when the brake pedal has been applied. The BCM monitors the brake pedal position sensor to determine when the brake pedal is applied. When the brake pedal is applied, the BCM supplies 12V on the stop lamp switch signal circuit and also sends a serial data message to the ECM indicating that the brake pedal has been applied.

The BCM detects a short to ground on the cruise/ETC/TCC brake signal circuit.

The cruise control system is disabled

  1. The DTC will be current for as long as the fault is present.
  2. When the fault is no longer present, the DTC will be a history DTC.
  3. A history DTC will clear after 50 ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition OFF, disconnect the X1 (LF1) or X2 (LAU) harness connector at the K20 ECM.
  2. Connect a test lamp between the signal circuit terminal listed below and ground: Terminal 57 (LF1) Terminal 52 (LAU)
  3. Ignition ON, observe the function of the test lamp while pressing and releasing the brake pedal. The test lamp should turn ON when the brake pedal is pressed and turn OFF when the brake pedal is released. If the test lamp is always ON, test the signal circuit for a short to voltage. If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance.
  4. If all circuits test normal, replace the K9 BCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup and programming

Symptoms - Lighting

Note. The following steps must be completed before using a symptom table.

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) before using a symptom table in order to verify that all of the following conditions are true: There are no DTCs set. The control modules can communicate via the serial data link.
  2. Review the system description and operation in order to familiarize yourself with the system functions. Refer to the following: «Exterior Lighting Systems Description and Operation»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) «Interior Lighting Systems Description and Operation»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)

Visual/Physical Inspection

  1. Inspect for aftermarket devices which could affect the operation of the lighting system. Refer to «Checking Aftermarket Accessories»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__checking-aftermarket-accessories) .
  2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Thoroughly inspect the wiring and connectors. An incomplete inspection of the wiring and connectors may result in misdiagnosis causing part replacement with the reappearance of the malfunction. If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

  1. «Adaptive Forward Lighting Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Backup Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Courtesy Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  4. «Daytime Running Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  5. «Front Fog Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  6. «Hazard Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  7. «Headlamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  8. «Headlamp Leveling Malfunction (RPO T84 or T85)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Headlamp Leveling Malfunction (RPO TT6, TT7 or TT8)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  9. «High Intensity Discharge Lamp Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  10. «Interior Accent Lighting Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  11. «Interior Backlighting Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  12. «Park, License, and/or Tail Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  13. «Rear Fog Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  14. «Stop Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  15. «Turn Signal Lamps and/or Indicators Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlight Leveling Control Module B+11
Headlamp Leveling Sensor 5V Reference - FrontB3415 021B3415 01
Headlamp Leveling Sensor 5V Reference - RearB3415 021B3415 01
Headlamp Leveling Sensor Signal - FrontB3410 06B3410 06B3410 01
Headlamp Leveling Sensor Signal - RearB3420 06B3420 06B3420 01
Headlamp Leveling Sensor Low Reference - FrontB3410 06
Headlamp Leveling Sensor Low Reference - RearB3415 02
Left Headlamp GroundU1511 00, U1521 00
Right Headlamp GroundU1512 00, U1522 00
1. All Headlamp Leveling Actuators Malfunction

Battery positive voltage is applied to the headlamp control module at all times. The headlamp control module has a normal operational voltage range of about 12.5-16 V and is only fully functional with the ignition switch is in the RUN position and the headlamp switch in the AUTOMATIC LIGHT position. The communications enable signal from the body control module (BCM) wakes the headlamp control module microprocessor. The headlamp control module receives serial data messages from the engine control module, transmission control module, electronic brake control module, and BCM with information regarding power mode, speed, steering angle, transmission gear selection, and headlamp switch status. The headlamp control module calculates the headlamp angle and sends commands to the left and right adaptive forward lighting system headlamp actuators. The headlamp actuators drive the headlamps to the position commanded by the headlamp control module. The headlamp control module monitors the headlamp actuator motor control circuits for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored in memory and the driver will be notified with a message displayed over the driver information center located on the instrument cluster.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition OFF, disconnect the inline harness connector listed below: M29L headlamp leveling actuator-left inline harness connector X111 M29R headlamp leveling actuator-right inline harness connector X112
  2. Test for less than 30 ohms between the ground circuit terminal A and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Engine running, test for less than 30 ohms between the ground circuit terminal E and ground. If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  4. Verify that a test lamp illuminates between the control circuit terminal D and ground. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  5. Test for 4.25 V-5.25 V between the signal circuit terminal M and ground. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K28 headlamp leveling control module.
  6. If all circuits test normal, test or replace the M29 headlamp leveling actuator

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for headlamp leveling control module replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
BCM B+1, 21, 2
Backup Lamp Supply VoltageB2545 02B2545 04B2545 01
Left Backup Lamp Ground1
Right Backup Lamp Ground2
1. Left Backup Lamp Inoperative 2. Right Backup Lamp Inoperative

When the engine is running and the transmission is placed in reverse gear, the transmission control module sends a serial data message to the body control module (BCM). The message indicates that the gear selector is in the reverse position. The BCM applies battery voltage to the backup lamps. Once the driver moves the gear selector out of the reverse position, a message is sent by the transmission control module via serial data requesting the BCM to remove battery voltage from the backup lamp signal circuit. The BCM will not apply battery voltage to the backup lamps if the engine is not running.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Engine running, command the Backup Lamps ON and OFF with a scan tool. The E5A backup lamp-left and the E5B backup lamp-right should turn ON and OFF when changing between the commanded states.

  1. If the E5A backup lamp-left or the E5B backup lamp-right is always OFF, inspect for a burned out bulb or corrosion of the bulb sockets.
  1. If the E5A backup lamp-left and the E5B backup lamp-right are always OFF or always ON, perform the Circuit/System Testing.
  1. Ignition OFF, disconnect the X2 harness connector K9 BCM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the X2 harness connector K9 BCM
  4. Disconnect the harness connector at the E5A backup lamp listed below: X3 harness connector E5E tail lamp-left (Without T79) X1 harness connector E5E tail lamp-left (With T79) X3 harness connector E5F tail lamp-right (Without T79) X1 harness connector E5F tail lamp-right (With T79)
  5. Test for less than 30 ohms between the ground circuit terminal listed below and ground. E5E tail lamp-left (Without T79) ground terminal 2 E5E tail lamp-left (With T79) ground terminal C E5F tail lamp-right (Without T79) ground terminal 2 E5F tail lamp-right (With T79) ground terminal C If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Connect a test lamp between the control circuit terminal listed below and ground: E5E tail lamp-left (Without T79) control terminal 1 E5E tail lamp-left (With T79) control terminal D E5F tail lamp-right (Without T79) control terminal 1 E5F tail lamp-right (With T79) control terminal D
  7. Engine running, command the Backup Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the selected states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  8. If all circuits test normal, test or replace the E5A backup lamp-left and the E5B backup lamp-right.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Backup Lamp Bulb Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Dome/Courtesy Lamp ControlB2615 0221
Courtesy Lamp Control2
1. Dome/Courtesy Lamps Always Illuminated 2. Dome/Courtesy Lamps do Not Illuminate

Battery voltage for the courtesy lamps is supplied at all times to the body control module (BCM). When the BCM receives a signal to command the courtesy lamps ON, it then applies voltage through the dome/courtesy lamps control circuit to the courtesy lamps.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the scan tool Door Ajar Switch parameter while opening and closing each vehicle door. The parameter should change between Inactive and Active. If the parameter does not change between the selected states, refer to «Door Ajar Indicator Malfunction»(/cadillac/srx/ii-2009-2012/remont/door-locks-anti-theft-systems/#door-lock-system-door-handles) .
  2. Observe the scan tool Rear Closure Ajar Switch parameter while opening and closing the rear liftgate. The parameter should change between Active and Inactive. If the parameter does not change between the selected states, refer to «Liftgate Ajar Indicator Malfunction (Manual Liftgate)»(/cadillac/srx/ii-2009-2012/remont/door-locks-anti-theft-systems/#door-lock-system-door-handles) or «Liftgate Ajar Indicator Malfunction (Power Liftgate)»(/cadillac/srx/ii-2009-2012/remont/door-locks-anti-theft-systems/#door-lock-system-door-handles) .
  3. Cycle the dome lamp switch while observing the scan tool Interior/Courtesy Lighting Master Switch parameter. The parameter should change between Cancel, ON and Door. If the parameter does not change, refer to Dome Lamp Switch Malfunction below.
  4. Command the Courtesy Lamps ON and OFF with a scan tool. The courtesy lamps should turn ON and OFF when changing between the commanded states. If the courtesy lamps do not turn ON and OFF when changing between the commanded states, refer to Courtesy Lamp Malfunction below.
  5. Command the Courtesy Lamps ON and OFF with a scan tool. The reading lamps should turn ON and OFF while changing between the commanded states. If the reading lamps do not turn ON and OFF when changing between the commanded states, refer to Reading Lamp Malfunction below.
  6. Command the Cargo Lamp ON and OFF with a scan tool. The cargo lamps should turn ON and OFF while changing between the commanded states. If the cargo lamps do not turn ON and OFF when changing between the commanded states, refer to Cargo Lamp Malfunction below.
  7. Turn the sunshade lamp ON and OFF by using the sunshade lamp switch. The sunshade lamp should turn ON and OFF while changing between the selected states. If the sunshade lamp does not turn ON and OFF when changing between the selected states, refer to Sunshade Illumination Malfunction below.
  8. Turn the instrument panel compartment lamp ON and OFF by using the instrument panel compartment lamp switch. The instrument panel compartment lamp should turn ON and OFF while changing between the selected states. If the instrument panel compartment lamp does not turn ON and OFF when changing between the selected states, refer to Instrument Panel Compartment Lamp Malfunction below.

Dome Lamp Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the S12 dome lamp switch.
  2. Scan tool disconnected, doors CLOSED, interior lamps OFF, test for less than 30 ohms between the ground circuit terminal 1 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Door. If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  4. Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Door. If not the specified value, test the signal circuit terminal 3 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  5. Connect a 3 A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Cancel. If not the specified value, test the signal circuit for a short to B+ or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. Connect a 3 A fused jumper wire between the signal circuit terminal 3 and ground. Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is On. If not the specified value, test the signal circuit for a short to B+ or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  7. If all circuits test normal, replace the S12 dome lamp switch.

Courtesy Lamp Malfunction

  1. Disconnect the harness connector at the appropriate courtesy lamp.
  2. Ignition OFF, scan tool OFF, doors CLOSED, interior lamps OFF, test for less than 5.0 ohms between the ground circuit terminal listed below and ground: Instrument Panel Courtesy Lamp - terminal 2 Door Courtesy Lamp - terminal 2 Overhead Console Courtesy/Reading Lamp - terminal 2 Rear Courtesy/Reading Lamp - terminal B If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal listed below and ground: Instrument Panel Courtesy Lamp - terminal 1 Door Courtesy Lamp - terminal 1 Overhead Console Courtesy/Reading Lamp - terminal 3 Rear Courtesy/Reading Lamp - terminal C
  4. Command the Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the courtesy lamp.

Reading Lamp Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate reading lamp.
  2. Test for less than 5 ohms between the ground circuit terminal listed below and ground. Overhead Console Courtesy/Reading Lamps - terminal 2 Rear Courtesy/Reading Lamps - terminal B If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Verify a test lamp illuminates between the control circuit terminal listed below and ground: Overhead Console Courtesy/Reading Lamps - terminal 1 Rear Courtesy/Reading Lamps - terminal A If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, test or replace the reading lamp.

Cargo Lamp Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate cargo lamp.
  2. Ignition OFF, scan tool OFF, doors CLOSED, interior lamps OFF, test for less than 5.0 ohms between the ground circuit terminal listed below and ground: Cargo Lamp - terminal 2 Liftgate Courtesy Lamp - terminal 2 If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal listed below and ground. The test lamp should turn ON when connected. Cargo Lamp - terminal 1 Liftgate Courtesy Lamp - terminal 1
  4. Command the Cargo Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the cargo lamp.

Sunshade Illumination Malfunction

  1. Ignition OFF, disconnect the harness connector at the A3 sunshade.
  2. Test for less than 5 ohms between the ground circuit terminal B and ground. If greater than the specified value, test the ground circuit for an open/high resistance.
  3. Verify a test lamp illuminates between the control circuit terminal A and ground. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, test or replace the A3 sunshade.

Instrument Panel Compartment Lamp Malfunction

  1. Ignition OFF, disconnect the harness connector at the E27 instrument panel compartment lamp.
  2. Open the instrument panel compartment.
  3. Verify that a test lamp illuminates between B+ and the ground circuit terminal 2. If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
  4. Verify a test lamp illuminates between the control circuit terminal 1 and ground. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the E27 instrument panel compartment lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. Refer to the appropriate replacement procedure for the lighting component that requires replacement.
  2. «Dome and Reading Lamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Ambient Light Sensor SignalB2645 03B2645 03B2645 07
Headlamp Switch Park Lamp Signal2B257A 002
Headlamp Switch On SignalB257A 0011
Headlamp Switch Headlamps Off SignalB257A 0011
Left Daytime Running Lamps ControlB2600 02B2600 04B2600 01
Right Daytime Running Lamps ControlB2605 02B2605 04B2605 01
Inside Air Temperature Sensor Low ReferenceB0163 05, B0183 05, B1405 05, B2645 07
Headlamp Switch Ground1
1. Headlight Auto Function Only 2. Headlight Auto Function Disabled

The ambient light sensor is used to monitor outside lighting conditions. The ambient light sensor provides a voltage signal that will vary between 1.4-4.5 V depending on outside lighting conditions. The body control module (BCM) monitors the ambient light sensor signal circuit to determine if outside lighting conditions are correct for either daytime running lights or automatic lamp control when the headlamp switch is in the AUTO position. In daylight conditions the BCM will command the daytime running lights ON. During low light conditions the BCM will command the low beam headlamps ON.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

  1. Ignition ON, observe the scan tool Ambient Light Sensor parameter. The reading should be between 1.4-4.5 V and change with ambient light changes. If greater or less than the specified range, refer to Ambient Light Sensor Malfunction below.
  2. Observe the scan tool Automatic Headlamp Disable Switch parameter while cycling the headlamp switch between the AUTOMATIC LIGHT and OFF positions. The parameter should cycle between Active and Inactive. If the value does not change, refer to Headlamp Switch Malfunction below.
  3. Observe the scan tool Headlamp ON Switch parameter while cycling the headlamp switch between the AUTOMATIC LIGHT and LOW BEAM ON position. The parameter should cycle between Active and Inactive. If the value does not change, refer to Headlamp Switch Malfunction below.
  4. Command the Left Dedicated Daytime Running Lamp and the Right Dedicated Daytime Running Lamp ON and OFF with a scan tool. The E4C daytime running lamp - left and the E4D daytime running lamp - right should turn ON and OFF while changing between the commanded states If the E4C daytime running lamp - left and the E4D daytime running lamp - right are always ON or always OFF, refer to Daytime Running Lamp Malfunction below.

Ambient Light Sensor Malfunction

  1. Ignition OFF, disconnect the harness connector at the B10B ambient light/sunload sensor.
  2. Test for less than 30 ohms between the low reference circuit terminal 6 and ground. If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K33 HVAC control module.
  3. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 5 and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, replace the B10B ambient light/sunload sensor.

Headlamp Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Ignition OFF, test for less than 30 ohms between the ground circuit terminal 6 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Park Lamps Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 3 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  4. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the ground circuit terminal 6. Verify the scan tool Park Lamps Switch is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. Verify the scan tool Headlamps On Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  6. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the ground circuit terminal 6. Verify the scan tool Headlamps On Switch is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  7. Verify the scan tool Automatic Headlamps Disable Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 5 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  8. Install a 3 A fused jumper wire between the signal circuit terminal 5 and the ground circuit terminal 6. Verify the scan tool Automatic Headlamps Disable Switch is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  9. If all circuits test normal, test or replace the S30 headlamp switch.

Daytime Running Lamp Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the K9 BCM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 3 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the X1 harness connector at the K9 BCM
  4. Ignition OFF, disconnect the appropriate inline harness connector listed below: E4C daytime running lamp - left X111 inline harness connector E4D daytime running lamp - right X116 inline harness connector
  5. Test for less than 30 ohms between the ground circuit terminal listed below and ground: Ground circuit terminal A Ground circuit terminal E If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Connect a test lamp between the control circuit terminal G and ground.
  7. Command the appropriate Dedicated Daytime Running Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K9 BCM.
  8. If all circuits test normal, replace the daytime running lamp bulb.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Sun Load Temperature and Daytime Running Lamp Ambient Light Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  4. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references)
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Switch Reference VoltageB257B 03B257B 03
Headlight Switch SignalB257B 03B257B 03B257B 07
Fog Lamp Relay ControlB2530 0212
Front Fog Lamp Control112
Right Front Fog Lamp Ground3
Left Front Fog Lamp Ground4
1. Front fog lamps inoperative 2. Front fog lamps always ON 3. Right front fog lamp inoperative 4. Left front fog lamp inoperative

The front fog lamp relay is supplied with battery voltage at all times. The front fog lamp switch signal circuit is grounded momentarily by pressing the front fog lamp switch. The body control module (BCM) energizes the front fog lamp relay by applying ground to the front fog lamp relay control circuit. When the front fog lamp relay is energized, the relay switch contacts close and battery voltage is applied through the front fog lamp fuse to the front fog lamp supply voltage circuit which illuminates the front fog lamps. With the front fog lamp switch activated the BCM sends a message via serial data to the instrument cluster requesting the instrument cluster to illuminate the front fog indicator.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the scan tool Front Fog Lamps Switch parameter. The parameter should change between Active and Inactive each time the front fog lamp switch is pressed. If the value does not change, refer to Fog Lamp Switch Malfunction below.
  2. Command the Fog Lamps ON and OFF with a scan tool. The front fog lamps should turn ON and OFF when changing between the commanded states. If the front fog lamps are always ON or always OFF, refer to Front Fog Lamp Malfunction below.

Fog Lamp Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Ignition ON, test for greater than 10V between the 12V reference circuit terminal 1 and ground. If less than the specified range, test the 12V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  3. Connect a 3A fused jumper wire between the 12V reference circuit terminal 1 and the signal circuit terminal 12, verify that the scan tool Front Fog Lamps Switch parameter is Active. If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM
  4. If all circuits test normal, test or replace the S30 headlamp switch.

Front Fog Lamp Malfunction

  1. Ignition OFF, disconnect the X2 harness connector at the X50A underhood fuse block.
  2. Connect a test lamp between the control circuit terminal 17 and B+.
  3. Command the Fog Lamps ON and OFF with a scan too. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. Ignition OFF, connect the X2 harness connector at the X50A underhood fuse block. Disconnect the harness connector at the E29 fog lamp-front.
  5. Test for less than 30 ohms between the ground circuit terminal B and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Connect a test lamp between the control circuit terminal A and ground.
  7. Ignition ON, command the Fog Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the X50A underhood fuse block. If the test lamp is always OFF and the circuit fuse is good, test the control circuit for an open/high resistance. If the circuit tests normal, replace the X50A underhood fuse block. If the test lamp is always OFF and the circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test or replace the E29 fog lamp-front
  8. If all circuits test normal, replace the E29 fog lamp-front.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Front Fog Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Fuse Block Replacement»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  3. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  4. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming.
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Switch Reference VoltageB257B 03B257B 03B3588 00
Headlight Switch SignalB257B 03B257B 03B257B 07
Rear Fog Lamps ControlB2540 0221
Tail Lamp Ground2
1. Rear fog lamp always ON 2. Rear fog lamp always OFF

The body control module (BCM) supplies a reference voltage to the backlight dimmer switch, which is part of the headlamp switch. When the backlight dimmer switch is placed in a desired brightness position, reference voltage is applied through the backlight dimmer switch resistor ladder to the BCM. The BCM interprets this voltage signal and will command the interior lights to the desired brightness, command the front fog lamps or the rear fog lamps depending upon the switch setting selected.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the scan tool Rear Fog Lamps Switch parameter. The parameter should change between Active and Inactive each time the rear fog lamp switch is pressed. If the value does not change, refer to Rear Fog Lamp Switch Malfunction below.
  2. Command the Rear Fog Lamp(s) Relay ON and OFF with a scan tool. The rear fog lamp should turn ON and OFF when changing between the commanded states If the rear fog lamps are always ON or always OFF, refer to Rear Fog Lamp Malfunction below.

Rear Fog Lamp Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Ignition OFF, test for 0.4K ohms to 1 ohms between the signal circuit terminal 12 and ground. If greater than the specified value, test the low reference circuit for an short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If less than the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the K9 BCM.
  3. Test for greater than 10V between the 12V reference circuit terminal 1 and ground. If less than the specified range, test the 12V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, replace the K9 BCM.

Rear Fog Lamp Malfunction

  1. Ignition OFF, disconnect the harness connector at the E5 fog lamp-rear.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal A and ground.
  4. Ignition ON, command the Rear Fog Lamp(s) Relay ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the E5 fog lamp-rear.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Tail Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming.
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Hazard Switch SignalB3596 0011
1. Hazard Function Inoperative

When the hazard switch is placed in the ON position, ground is momentarily applied through the hazard switch signal circuit to the body control module (BCM). The BCM will detect this voltage drop and will supply battery voltage to all four turn signal lamps in an ON and OFF duty cycle. When the hazard switch is activated, the BCM sends a serial data message to the instrument panel cluster (IPC) requesting both turn signal indicators to be cycled ON and OFF.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Observe the function of the right and left turn signal lamps while turning the hazard lamp switch ON and OFF. The right and left turn signal lamps should cycle ON and OFF while the hazard lamp switch is ON and remain OFF when the hazard lamp switch is OFF.

  1. Ignition OFF, disconnect the harness connector at the P17 info display module.
  2. Ignition ON, test for greater than 10V between the signal circuit terminal 16 and ground. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  3. If all circuits test normal, replace the P17 info display module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Radio Control Assembly Replacement»(/cadillac/srx/ii-2009-2012/remont/entertainment-systems/#cellular-systems-entertainment-systems-navigation-systems)
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Low Beam Relay B+B258A 04B258A 04
Headlamp Low Beam Relay ControlB258A 02B258A 04B258A 01
Left Low Beam Headlamp Control221
Right Low Beam Headlamp Control221
1. Headlamps Always ON 2. Headlamps Always OFF

When the headlight switch is placed in low beam position, the body control module (BCM) energizes the low beam headlamp relay which supplies battery voltage to the respective headlamp control circuits.

Diagnostic Aids

The following symptoms are noticeable signs of bulb failure

  1. Flickering light, caused in the early stages of bulb failure.
  2. Lights go out, caused when the ballast detects excessive, repetitive bulb re-strike.
  3. Color change-The lamp may change to a dim pink glow.
  4. Refer to «Exterior Lighting Systems Description and Operation»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) for more information on when to change the HID bulb.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the Headlamp Low Beam ON and OFF with a scan tool. The E4G headlamp-left low beam and the E4H headlamp-right low beam should turn ON and OFF when changing between the commanded states.

WARNINGThe high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
  1. Ignition OFF, disconnect the KR49 headlamp low beam relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 30 and ground. If the test lamp illuminates, test the control circuit for a short to voltage.
  3. Verify that a test lamp illuminates between the B+ circuit terminal 87 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance
  4. Verify that a test lamp illuminates between the B+ circuit terminal 86 and ground. If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  5. Connect a 20 A fused jumper wire between the B+ circuit terminal 87 and the control circuit terminal 30. Verify the E4G headlamp-left low beam and the E4H headlamp-right low beam are activated. If the E4G headlamp-left low beam or the E4H headlamp-right low beam do not activate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the appropriate E4 headlamp-low beam
  6. Connect a test lamp between the B+ circuit terminal 86 and the control circuit terminal 85.
  7. Ignition ON, command the Low Beam Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  8. If all circuits test normal, test or replace the KR49 headlamp low beam relay.

Relay Test

  1. Ignition OFF, disconnect the KR49 headlamp low beam relay.
  2. Test for 60-180 ohms between terminals 85 and 86. If not within the specified range, replace the KR49 headlamp low beam relay.
  3. Test for infinite resistance between the following terminals: 30 and 86 30 and 87 30 and 85 85 and 87 If not the specified value, replace the KR49 headlamp low beam relay.
  4. Install a 15A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87. If greater than the specified range, replace the KR49 headlamp low beam relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Ballast Replacement (TT6, TT7, TT8)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Headlamp Capsule Replacement (TT6, TT7, TT8)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__headlamp-capsule-replacement-tt6-tt7-tt8)
  4. «Relay Replacement (Attached to Wire Harness)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  5. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Ambient Light Sensor SignalB2645 03B2645 03B2645 07
Headlamp Switch Park Lamp Signal2B257A 002
Headlamp Switch On SignalB257A 0011
Headlamp Switch Headlamps Off SignalB257A 0011
Left Headlamp ControlB2575 02B2575 04B2575 01
Right Headlamp ControlB2699 02B2699 04B2699 01
Inside Air Temperature Sensor Low ReferenceB0163 05, B0183 05, B1405 05, B2645 07
Headlamp Switch Ground1
1. Headlight Auto Function Only 2. Headlight Auto Function Disabled

The vehicle headlamps are controlled by the body control module (BCM) based on inputs from the headlamp switch and the turn signal/multifunction switch. The headlamp switch has four positions: OFF, AUTOMATIC LIGHT, PARKING LIGHT, and LOW BEAM. The default headlamp switch position is AUTOMATIC LIGHT, in which the BCM uses the ambient light sensor to determine when headlamps are needed. The OFF portion of the headlamp switch is a momentary switch which overrides the automatic headlamp and will turn OFF the vehicle headlamps. When in the OFF position, the headlamp switch grounds the headlamp switch headlamps OFF signal circuit, prompting the BCM to turn OFF the headlamps. The Park position of the headlamp switch will only illuminate the vehicle parking lamps. The LOW BEAM position of the headlamp switch will illuminate both the parking lamps, as well has the headlamps. With the headlamp switch in the LOW BEAM position, the headlamp switch headlamps on signal circuit is grounded, prompting the BCM to turn on the headlamps, regardless of other factors such as ambient light.

The headlamp high beams are controlled through the flash to pass switch and the headlamp dimmer switch, both located in the turn signal/multifunction switch. The flash to pass switch is a momentary type switch, designed to illuminate the high beams as long as the switch is held. With the switch closed, the flash to pass switch signal circuit is grounded, prompting the BCM to turn on the high beam lamps. The headlamp dimmer switch allows the operator to select between full time high or low beam operation. Unlike the flash to pass switch, it is not a momentary switch. When the headlamp dimmer switch is in the high beam position, the headlamp dimmer switch high beam signal circuit is grounded. This prompts the BCM to turn on the high beam lamps.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the scan tool Ambient Light Sensor parameter. The reading should be between 1.4-4.5 V and change with ambient light changes. If greater or less than the specified range, refer to Ambient Light Sensor Malfunction below.
  2. Observe the scan tool Automatic Headlamp Disable Switch parameter while cycling the headlamp switch between the AUTOMATIC LIGHT and OFF positions. The parameter should cycle between Active and Inactive. If the value does not change, refer to Headlamp Switch Malfunction below.
  3. Observe the scan tool Headlamp ON Switch parameter while cycling the headlamp switch between the AUTOMATIC LIGHT and LOW BEAM ON position. The parameter should cycle between Active and Inactive. If the value does not change, refer to Headlamp Switch Malfunction below.
  4. Observe the function of the E4G headlamp-left low beam and the E4F headlamp-right low beam while commanding the low beam lamps ON and OFF with a scan tool. The E4G headlamp-left low beam and the E4F headlamp-right low beam should turn ON and OFF while changing between the commanded states If the E4G headlamp-left low beam and the E4F headlamp-right low beam are always ON or always OFF, refer to Low Beam Headlamp Malfunction below.
  5. Observe the scan tool High Beam Select Switch parameter while selecting the S78 turn signal/multifunction switch between the high beam position and the low beam position. The value should change between Inactive and Active while selecting between the two positions. If a value does not change between the commanded states, refer to Turn Signal/Multifunction Switch Malfunction below.
  6. Observe the scan tool Headlamps Flash Switch parameter while pulling and releasing the S78 turn signal/multifunction switch. The value should be Inactive and change to Active as the switch is pulled and released If a value does not change between the commanded states, refer to Turn Signal/Multifunction Switch Malfunction below.
  7. Command the High Beams ON and OFF with a scan tool. The E4E headlamp-left high beam and the E4F right high beam should turn ON and OFF when changing between the selected states. If the E4E headlamp-left high beam or the E4F right high beam low beam is always OFF, refer to High Beam Headlamps Inoperative below. If both high beam headlamps are always ON or always OFF, refer to High Beam Command Malfunction below.
  1. Ignition OFF, disconnect the harness connector at the B10B ambient light/sunload sensor.
  2. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 5 and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  3. If all circuits test normal, replace the B10B ambient light/sunload sensor.
  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Ignition OFF, test for less than 30 ohms between the ground circuit terminal 6 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Park Lamps Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 3 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  4. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the ground circuit terminal 6. Verify the scan tool Park Lamps Switch is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. Verify the scan tool Headlamps On Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  6. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the ground circuit terminal 6. Verify the scan tool Headlamps On Switch is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  7. Verify the scan tool Automatic Headlamps Disable Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 5 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  8. Install a 3 A fused jumper wire between the signal circuit terminal 5 and the ground circuit terminal 6. Verify the scan tool Automatic Headlamps Disable Switch is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  9. If all circuits test normal, test or replace the S30 headlamp switch.

Low Beam Headlamp Malfunction

  1. Ignition OFF, disconnect the harness X1 harness connector at the K9 BCM.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal listed below and ground: B+ circuit terminal 3 B+ circuit terminal 4 If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the harness X1 harness connector at the K9 BCM.
  4. Disconnect the inline harness connector at the appropriate E4 headlamp-low beam listed below: E4G headlamp-left low beam X115 inline harness connector E4F headlamp-right low beam X116 inline harness connector
  5. Connect a test lamp between the control circuit terminal G and ground.
  6. Ignition ON, command the low beam lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF while changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM
  7. If all circuits test normal, replace the headlamp bulb or the headlamp.

Turn Signal/Multifunction Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the S78 turn signal/multifunction switch.
  2. Ignition OFF, test for less than 30 ohms between the ground circuit terminal 3 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Headlamps Flash Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  4. Install a 3 A fused jumper wire between the signal circuit terminal 4 and ground. Verify the scan tool Headlamps Flash Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. Verify the scan tool High Beam Select Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  6. Install a 3 A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool High Beam Select Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the K9 BCM.
  7. If all circuits test normal, test or replace the S78 turn signal/multifunction switch.

High Beam Headlamps Inoperative

  1. Connect a 10A fused jumper wire between the HI BEAM-LT fuse test point and B+. Verify that the E4E headlamp-left high beam is illuminated. If the E4E headlamp-left high beam does not illuminate, test the control circuit terminal 27 X3 at the X50A fuse block-underhood for a short to ground or an open/high resistance. If the circuit tests normal, replace the E4E headlamp-left high beam.
  2. Connect a 10A fused jumper wire between the HI BEAM-RT fuse test point and B+. Verify that the E4F headlamp-right high beam is illuminated. If the E4F headlamp-right high beam does not illuminate, test the control circuit terminal 26 X3 at the X50A fuse block-underhood for a short to ground or an open/high resistance. If the circuit tests normal, replace the E4F headlamp-right high beam.

High Beam Command Malfunction

  1. Ignition OFF, disconnect the X5 harness connector at the K9 BCM.
  2. Ignition ON, test for greater than 10V between the control circuit terminal 18 and ground. If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50A fuse block-underhood.
  3. Connect a 5A fused jumper wire between the control circuit terminal 18 and ground. Verify that the E4E headlamp-left high beam and the E4F right high beam is illuminated. If the E4E headlamp-left high beam and the E4F right high beam is not illuminated, test the control circuit for a short to voltage. If the circuit tests normal, replace the X50A fuse block-underhood.
  4. If all circuits test normal, replace the K9 BCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Sun Load Temperature and Daytime Running Lamp Ambient Light Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  4. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references)
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Leveling Switch Ignition11
Left Headlamp Leveling Ignition22
Right Headlamp Leveling Ignition33
Left Headlamp Leveling Control222
Right Headlamp Leveling Control333
Left Headlamp Ground2
Right Headlamp Ground3
1. All Headlamp Leveling Actuator Malfunction 2. Left Headlamp Leveling Actuator Malfunction 3. Right Headlamp Leveling Actuator Malfunction

Each headlamp assembly contains a headlamp leveling motor that is controlled by the headlight switch. The headlight switch is a resistance ladder switch and wired to the headlamp leveling motors. With the ignition in ON position the headlight switch ON, the headlamp leveling motors are supplied with a specific voltage depending upon the position of the headlamp leveling switch. With the switch in the 0 position, no voltage is supplied to the headlamp leveling motors and the headlamp aiming will be at the factory specifications. Each switch selection will provide the headlamp leveling motors with incrementally increased voltage levels changing the headlamp aiming.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  2. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  3. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
  4. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)

Ignition ON, headlamps ON, observe the function of the left and right headlamps while selecting each level position on the headlamp level switch. The left and right headlamps should move as each position is selected.

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 9 and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the harness connector at the S30 headlamp switch and disconnect the inline harness connector listed below: M29L headlamp leveling actuator-left inline harness connector X115 M29R headlamp leveling actuator-right inline harness connector X116
  4. Test for less than 30 ohms between the ground circuit terminal E and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  5. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal D and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
  6. Connect a test lamp between the control circuit terminal F and ground.
  7. Ignition ON, headlamps ON, command each headlamp level function by using the headlamp leveling switch. The test lamp should illuminate and change intensity while changing between the commanded states. If the test lamp is always OFF, test the control circuit for a short to ground or an open. If the circuit tests normal, test or replace the S30 headlamp switch. If the test lamp is always ON or does not change intensity, test the control circuit for a short to voltage or for high resistance. If the circuit tests normal, test or replace the S30 headlamp switch.
  8. If all circuits test normal, replace the M29 headlamp leveling actuator.
  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. With the headlamp leveling switch in position 0, test for 2.2-2.4 k ohms between the ignition terminal 9 and control terminal 10. If not within the specified range, replace the S30 headlamp switch.
  3. With the headlamp leveling switch in position 1, test for 1.9-2.1 k ohms between the ignition terminal 9 and control terminal 10. If not within the specified range, replace the S30 headlamp switch.
  4. With the headlamp leveling switch in position 2, test for 1.7-1.9 k ohms between the ignition terminal 9 and control terminal 10. If not within the specified range, replace the S30 headlamp switch.
  5. With the headlamp leveling switch in position 3, test for 1.4-1.6 kohms between the ignition terminal 9 and control terminal 10.. If not within the specified range, replace the S30 headlamp switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Ignition Left Headlamp22B1461 00
Ignition Right Headlamp33B1462 00
Headlamp Leveling Sensor 5V Reference - FrontB3415 021B3415 01
Headlamp Leveling Sensor 5V Reference - RearB3415 021B3415 01
Headlamp Leveling Sensor Signal - FrontB3410 06B3410 06B3410 01
Headlamp Leveling Sensor Signal - RearB3420 06B3420 06B3420 01
Headlamp Leveling Sensor Low Reference - Front1
Headlamp Leveling Sensor Low Reference - Rear1
Left Headlamp Ground2B1461 00
Right Headlamp Ground3B1462 00
1. All Headlamp Leveling Actuator Malfunction 2. Left Headlamp Leveling Actuator Malfunction 3. Right Headlamp Leveling Actuator Malfunction

Battery positive voltage is applied to the headlamp control module at all times. The headlamp control module has a normal operational voltage range of about 12.5-16 V and is only fully functional with the ignition switch is in the RUN position and the headlamp switch in the AUTOMATIC LIGHT position. The communications enable signal from the body control module (BCM) wakes the headlamp control module microprocessor. The headlamp control module receives serial data messages from the engine control module (ECM), transmission control module (TCM), electronic brake control module (EBCM), and BCM with information regarding power mode, speed, steering angle, transmission gear selection, and headlamp switch status. The headlamp control module calculates the headlamp angle and sends commands to the left and right adaptive forward lighting system headlamp actuators. The headlamp actuators drive the headlamps to the position commanded by the headlamp control module. The headlamp control module monitors the headlamp actuator motor control circuits for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored in memory and the driver will be notified with a message displayed over the driver information center located on the instrument cluster.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Headlamp Leveling Sensor Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate B51 headlamp leveling sensor.
  2. Test for less than 5 ohms between the low reference circuit terminal 3 and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  3. Ignition ON, test for 4.8-5.2 V between the 5V reference circuit terminal 1 and ground. If less than the specified range, test the 5V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module. If greater than the specified range, test the 5V reference circuit for a short to voltage. If the circuit tests normal, replace the K28 headlamp leveling control module.
  4. Verify the appropriate scan tool Leveling Position Sensor parameter is 0 V. If greater than the specified range, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the K28 headlamp leveling control module.
  5. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the 5V reference circuit terminal 1. Verify the appropriate scan tool Leveling Position Sensor parameter is greater than 5 V. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  6. If all circuits test normal, replace the B51 headlamp leveling sensor.

Headlamp Leveling Actuator Malfunction

  1. Ignition OFF, disconnect the inline harness connector listed below: M29L headlamp leveling actuator-left inline harness connector X111 M29R headlamp leveling actuator-right inline harness connector X112
  2. Test for less than 30 ohms between the ground circuit terminal A and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Engine running, test for less than 30 ohms between the ground circuit terminal E and ground. If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  4. Verify that a test lamp illuminates between the control circuit terminal D and ground. If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module.
  5. Test for 4.25 V-5.25 V between the signal circuit terminal M and ground. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K28 headlamp leveling control module. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K28 headlamp leveling control module.
  6. If all circuits test normal, test or replace the M29 headlamp leveling actuator.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Headlamp Leveling Front Suspension Height Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Headlamp Leveling Rear Suspension Height Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  4. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for module replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Accent Lamp Control112
Accent Lamp Ground1
1. Interior Accent Lighting Inoperative 2. Interior Accent Lighting Always ON

The body control module (BCM) uses the ambient light sensor to determine which brightness of the accent lamps is needed. The BCM provides B+ voltage to the individual accent lamps via the accent lamps control circuit.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the Accent Lighting ON and OFF with a scan tool. The accent lighting should turn ON and OFF when changing between the commanded sates.

  1. Ignition OFF, disconnect the harness connector at the appropriate E1 accent lamp.
  2. Test for less than 5.0 ohms between the ground circuit terminal and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal and ground.
  4. Ignition ON, command the Accent Lighting ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the E1 accent lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. Refer to the appropriate replacement procedure for the lighting component that requires replacement.
  2. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Headlamp Switch B+B1405 03, B1529 03, B257B 03, 1B257B 03, 1
Instrument Panel Lamps Dimmer Switch SignalB257B 03, 1B257B 03, 1B257B 07
Interior Backlighting Control BCM Terminal 9 X7B2625 0221
Interior Backlighting Control BCM Terminal 8 X2B2625 02, 221
Interior Backlighting Control BCM Terminal 5 X1 (with UD5)B2625 0221
Headlamp Switch GroundB257B 03
1. Interior backlighting at full intensity and cannot be dimmed 2. Interior backlighting component does not illuminate

The dimmer switch is used to increase and decrease the brightness of the interior backlighting components. The body control module (BCM) supplies a reference voltage to the backlight dimmer switch, which is part of the headlamp switch. When the dimmer switch is placed in a desired brightness position, the dimmed voltage setting is applied through the dimmer switch and the dimmer switch signal circuit to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage through the backlight lamp control circuit and the LED dimming control circuit illuminating the components to the requested level.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the scan tool Indicator Dimming Duty cycle Command parameter while operating the dimmer switch from high to low. The parameter should change between 5-50% when the backlight switch is moved up and down. If the reading does not change, refer to the Dimmer Switch Circuit Test below.
  2. Observe the interior backlighting components while commanding the LED Backlight Dimming ON and OFF with the scan tool. The backlighting should turn ON and OFF when changing between the commanded states. If the backlighting does not change between the commanded states, refer to the Interior Backlighting Circuit Test below.

Dimmer Switch Circuit Test

  1. Ignition OFF, disconnect the harness connector at the S30 headlamp switch.
  2. Test for less that 10 ohms between the ground circuit terminal 6 and ground. If greater than the specified range, test the ground circuit for an open high/resistance.
  3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. Ignition ON, test for less than 0.3 V between signal circuit terminal 12 and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the B+ circuit terminal 1. The interior backlighting should be dimmed. If the interior backlighting is not dimmed, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. If all circuits test normal, test or replace the S30 headlamp switch.

Interior Backlighting Circuit Test

  1. Ignition OFF, disconnect the harness connector at the appropriate backlighting component.
  2. Test for less than 5.0 ohms between the ground circuit terminal and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal and ground.
  4. Ignition ON, command the LED Backlight Dimming ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the component with the inoperative backlighting.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Headlamp Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. Refer to the appropriate replacement procedure for the lighting component that requires replacement.
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, setup and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Park Lamp Supply VoltageB2585 02B2585 04B2585 01
Right Park Lamp Supply VoltageB3867 02B3867 01, B3867 04B3867 01
License Plate Lamp ControlB3883 02B3883 04B3883 01
Left Headlamp Lamp Ground1
Left Tail Lamp Ground2
Left License Plate Lamp Ground3
Right Headlamp Lamp Ground4
Right Tail Lamp Ground5
Right License Plate Lamp Ground6
1. Left Front Side Marker Lamp Inoperative 2. Left Rear Side Marker Lamp Inoperative 3. Left License Plate Lamp Inoperative 4. Right Front Side Marker Lamp Inoperative 5. Right Rear Side Marker Lamp Inoperative 6. Right License Plate Lamp Inoperative

The park lamps, tail lamps and license plate lights are turned ON when the headlamp switch is placed in the PARK or LOW BEAM position or anytime the headlights are requested. When the body control module (BCM) receives a request from the headlamp switch to turn ON the park lamps the BCM a sends out a voltage on the control circuit, which illuminates the park lamps, tail lamps and license plate lights.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the function of the E2LF side marker lamp-left front, E5E tail lamp-left rear and the E4J park lamp-left front while commanding the Left Park Lamps ON and OFF with a scan tool. The E2LF side marker lamp-left front, E5E tail lamp-left rear and the E4J park lamp-left front should turn ON and OFF while changing between the commanded states If the E2LF side marker lamp-left front, E5E tail lamp-left rear and the E4J park lamp-left front are always ON or always OFF, refer to Left Side Marker/Tail Lamps Malfunction below.
  2. Ignition ON, observe the function of the E2RF side marker lamp-right front, E5F tail lamp-right rear and the E4K park lamp-right front while commanding the Right Park Lamps ON and OFF with a scan tool. The E2RF side marker lamp-right front, E5F tail lamp-right rear and the E4K park lamp-right front should turn ON and OFF while changing between the commanded states. If the E2RF side marker lamp-right front, E5F tail lamp-right rear and the E4K park lamp-right front are always ON or always OFF, refer to Right Side Marker/Tail Lamps Malfunction below.
  3. Observe the function of the E7L license plate lamp-left and E7R license plate lamp-right while commanding the license plate lamps ON and OFF with a scan tool. The E7L license plate lamp-left and E7R license plate lamp-right should turn ON and OFF when changing between the commanded states If the E7L license plate lamp-left or E7R license plate lamp-right is always OFF, inspect for a burned out bulb or corrosion of the bulb sockets. If the E7L license plate lamp-left and E7R license plate lamp-right are always OFF or always ON, refer to License Plate Lamp Malfunction below.
  1. Disconnect the X1 harness connector at the E5E tail lamp-left.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Disconnect the appropriate inline harness connector listed below: X111 inline harness connector (With TT6/TT7/TT8) X115 inline harness connector (Without TT6/TT7/TT8)
  4. Test for less than 30 ohms between the ground circuit terminal listed below and ground: Ground circuit terminal A Ground circuit terminal E If greater than the specified range, test the ground circuit for an open/high resistance.
  5. Connect a test lamp between the control circuit terminal listed below and ground. E2LF side marker lamp-left front control circuit terminal K E4J park lamp-left front control circuit terminal B E5E tail lamp-left control circuit terminal B
  6. Ignition ON, command the Left Park Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K9 BCM.
  7. If all the circuits test normal, replace the appropriate left marker lamp.
  1. Disconnect the X1 harness connector at the E5F tail lamp-right.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition OFF, disconnect the appropriate inline harness connector listed below: X112 inline harness connector (With TT6/TT7/TT8) X116 inline harness connector (Without TT6/TT7/TT8)
  4. Test for less than 30 ohms between the ground circuit terminal listed below and ground: Ground circuit terminal A Ground circuit terminal E If greater than the specified range, test the ground circuit for an open/high resistance.
  5. Connect a test lamp between the control circuit terminal listed below and ground. E2RF side marker lamp-right front control circuit terminal K E4K park lamp-right front control circuit terminal B E5F tail lamp-right control circuit terminal A
  6. Ignition ON, command the Right Park Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K9 BCM.
  7. If all the circuits test normal, replace the appropriate right marker lamp

License Plate Lamp Malfunction

  1. Ignition OFF, disconnect the X902 inline harness connector.
  2. Test for less than 30 ohms between the ground circuit terminal 15 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal 1 and ground.
  4. Ignition ON, command the license plate lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the selected states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the E7L license plate lamp-left or E7R license plate lamp-right.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Tail Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  2. «Front Turn Signal Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Front Turn Signal Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__front-turn-signal-lamp-bulb-replacement) or «Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Liftgate Center Applique Replacement»(/cadillac/srx/ii-2009-2012/remont/exteriorinterior-trim/#exterior-trim)
  4. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Brake Apply Sensor 5 V ReferenceC0890 03, C0277 06C0277 06C0277 07
Brake Apply Sensor SignalC0277 06C0277 06C0277 07
Center High Mounted Stop Lamp ControlB3884 0212
Left Brake Lamps ControlB3881 0212
Right Brake Lamp ControlB3882 0212
Brake Apply Sensor Low ReferenceC0277 07
Center High Mounted Stop Lamp Ground1
Left Tail Lamp Ground1
Right Tail Lamp Ground1
1. Stop Lamps Inoperative 2. Stop Lamps Always ON

The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an analog voltage signal that will increase as the brake pedal is applied. The body control module (BCM) provides a low reference signal and a 5 V reference voltage to the brake pedal position sensor. When the variable signal reaches a voltage threshold indicating the brakes have been applied, the BCM will apply battery voltage to the stop lamp control circuit and center high mounted stop lamp control circuit. When the control circuit is energized the stop lamps are illuminated.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the scan tool Brake Pedal Position Sensor parameter while applying and releasing the brake pedal. The value should be 0.2 V with the pedal pressed and 0 V with the pedal released. If the value does not change, refer to the Brake Pedal Position Sensor Malfunction below.
  2. Observe function of the E5L stop lamp- left while commanding the Left Brake Lamp ON and OFF with a scan tool. The E5L stop lamp- left should turn ON and OFF when changing between the selected states. If the E5L stop lamp- left is always ON or always OFF, refer to Left Brake Lamp Malfunction below.
  3. Observe function of the E5R stop lamp- right while commanding the Right Brake Lamp ON and OFF with a scan tool. The E5R stop lamp- right should turn ON and OFF when changing between the selected states. If the E5R stop lamp- right is always ON or always OFF, refer to Right Brake Lamp Malfunction below.
  4. Observe function of the E6 center high mounted stop lamp while commanding the Center Brake Lamp ON and OFF with a scan tool. The E6 center high mounted stop lamp should turn ON and OFF when changing between the selected states. If the E6 center high mounted stop lamp is always ON or always OFF, refer to Center High Mount Stop Lamp Malfunction below.

Brake Pedal Position Sensor Malfunction

  1. Ignition OFF, disconnect the harness connector at the B22 brake pedal position sensor.
  2. Ignition OFF, test for less than 30 ohms between the low reference circuit terminal C and ground. If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  3. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal A and ground. If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  4. Verify that the scan tool Brake Pedal Position Sensor parameter is less than 0.3 V. If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. Connect a 3 A fused jumper wire between the 5 V reference circuit terminal A and the signal circuit terminal B. Verify that the scan tool Brake Pedal Position Sensor parameter is 4.8-5.2 V If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. If all circuits test normal, test or replace the B22 brake pedal position sensor.

Left Brake Lamp Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the E5E tail lamp-left.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal A and ground.
  4. Ignition ON, command the Left Brake Lamp ON and OFF with a scan tool, the test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the E5E tail lamp-left.

Right Brake Lamp Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the E5F tail lamp-right.
  2. Test for less than 30 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal A and ground.
  4. Ignition ON, command the Right Brake Lamp ON and OFF with a scan tool, the test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, test or replace the E5F tail lamp-right.

Center High Mount Stop Lamp Malfunction

  1. Ignition OFF, disconnect the harness connector at the E6 center high mounted stop lamp.
  2. Test for less than 30 ohms between the ground circuit terminal B and ground. If greater than the specified value, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal A and ground.
  4. Ignition ON, command the Center Brake Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If all circuits test normal, replace the E6 center high mounted stop lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Brake Pedal Position Sensor Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__brake-pedal-position-sensor-replacement)
  2. «Brake Pedal Position Sensor Calibration»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__brake-pedal-position-sensor-calibration)
  3. «Tail Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  4. «High Mount Stop Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  5. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Trailer Park Lamp Relay B+B388A 04B388A 04
Left Trailer Turn Signal Lamp ControlB3887 02B3887 041
Right Trailer Turn Signal Lamp ControlB3888 02B3888 042
Park Lamp Supply Voltage/Marker Lamp Supply VoltageB388A 02B388A 04B388A 01
1. Left Trailer Turn Signal Lamp Inoperative 2. Right Trailer Turn Signal Lamp Inoperative

The trailer park lamp relay is supplied with battery voltage at all times. The trailer park lamp signal circuit is grounded by turning the headlamp switch. The body control module (BCM) energizes the trailer park lamp relay by applying ground to the trailer park lamp relay control circuit. When the trailer park lamp relay is energized, the relay switch contacts close and battery voltage is applied through the trailer park lamp relay fuse to the trailer park lamp supply voltage circuit which illuminates the trailer park lamps if a trailer is connected.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the function of the left trailer turn signal lamp and the right trailer turn signal lamp while commanding the Left Trailer Turn Signal Lamp and the Right Trailer Turn Signal Lamp ON and OFF with a scan tool. The left trailer turn signal lamp and the right trailer turn signal lamp should turn ON and OFF while changing between the commanded states. If the left or right trailer turn signal lamp is always ON or always OFF, refer to Trailer Turn Signal Lamps Malfunction below.
  2. Observe the function of the trailer tail lamps while commanding the Trailer Park Lamps ON and OFF with a scan tool. The trailer tail lamps should turn ON and OFF while changing between the commanded states. If the trailer parks lamps are always ON or always OFF, refer to Trailer Park Lamps Malfunction below.

Trailer Turn Signal Lamps Malfunction

  1. Ignition OFF, disconnect the X5 harness connector at the K9 BCM.
  2. Ignition ON, test for greater than 10 V between the control circuit terminal listed below and ground: Right trailer turn signal lamp control terminal 17 Left trailer turn signal lamp control terminal 8 If less than the specified value, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50A fuse block-underhood.
  3. Connect a 10 A fused jumper wire between the trailer turn signal lamp fused test point and B+. Verify that the appropriate trailer turn signal lamp is illuminated. If the trailer turn signal lamp is not illuminated, test the control circuit listed below for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50A fuse block-underhood. Control terminal 43 X2 at the X50A fuse block-underhood. Control terminal 67 X2 at the X50A fuse block-underhood.
  4. If all the circuits test normal, replace the K9 BCM.

Trailer Park Lamps Malfunction

  1. Ignition OFF, disconnect the trailer park lamp relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground. If the test lamp illuminates, test the control circuit for a short to voltage
  3. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 86 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Verify a test lamp illuminates between the B+ circuit terminal 30 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the trailer park lamp relay.
  5. Connect a 15 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the trailer park lamps are activated. If the trailer park lamps do not activate, test the control circuit for an open/high resistance. If the circuit tests normal, replace the trailer park lamps.
  6. Connect a test lamp between the control circuit terminal 85 and the B+ circuit terminal 86.
  7. Command the Trailer Park Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM.
  8. If all circuits test normal, test or replace the trailer park lamp relay.
  1. Ignition OFF, disconnect the trailer park lamp relay.
  2. Test for 60-180 ohms between terminals 85 and 86. If not within the specified range, replace the trailer park lamp relay.
  3. Test for infinite resistance between the following terminals: 30 and 86 30 and 87 30 and 85 85 and 87 If not the specified value, replace the trailer park lamp relay.
  4. Install a 5 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87. If greater than the specified range, replace the trailer park lamp relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Relay Replacement (Attached to Wire Harness)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) or «Relay Replacement (Within an Electrical Center)»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  2. «Fuse Block Replacement»(/cadillac/srx/ii-2009-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions)
  3. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Trailer Brake Control Module B+B1325 03B1325 03
Center High Mounted Stop Lamp Signal555B0655 5A
Backup Lamps ControlB3890 02B3890 042
Stop Lamps ControlB3889 02B3889 045
Left Turn Signal Lamps ControlB3887 02B3887 046
Right Turn Signal Lamps ControlB3888 02B3888 047
Trailer Fog Lamp ControlB3891 02B3891 043
Trailer Left Park Lamp ControlB3885 02B3885 044
Trailer Right Park Lamp ControlB3886 02B3886 044
Trailer Brake Control Module Ground1
Trailer Connector Ground1
1. All Trailer Lamps Inoperative 2. Trailer Backup Lamps Malfunction 3. Trailer Fog Lamps Malfunction 4. Trailer Park/Tail Lamps Malfunction 5. Trailer Brake Lamps Malfunction 6. Trailer Left Turn Signal Lamp Malfunction 7. Trailer Right Turn Signal Lamp Malfunction

The trailer brake control module will receive a serial data message from the BCM indicating when each of the vehicle exterior lights have been activated. The trailer brake control module will then apply voltage to the appropriate trailer lamps through their respective voltage supply circuits.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the function of the left trailer tail lamp and the right trailer tail lamp while commanding the Left Trailer Tail Lamp and the Right Trailer Tail Lamp ON and OFF with a scan tool. The left trailer tail lamp and the right trailer tail lamp should turn ON and OFF while changing between the commanded states. If the left trailer tail lamp or the right trailer tail lamp is always ON or always OFF, refer to Trailer Lamps Malfunction below.
  2. Observe the function of the left trailer turn signal lamp and the right trailer turn signal lamp while commanding the Left Trailer Turn Signal Lamp and the Right Trailer Turn Signal Lamp ON and OFF with a scan tool. The left trailer turn signal lamp and the right trailer turn signal lamp should turn ON and OFF while changing between the commanded states. If the left trailer turn signal lamp or the right trailer turn signal lamp is always ON or always OFF, refer to Trailer Lamps Malfunction below.
  3. Observe the function of the trailer fog lamps while commanding the Trailer Fog Lamps ON and OFF with a scan tool. The trailer fog lamps should turn ON and OFF while changing between the commanded states. If the trailer fog lamps are always ON or always OFF, refer to Trailer Lamps Malfunction below.
  4. Observe the function of the trailer backup lamps while commanding the Trailer Backup Lamps ON and OFF with a scan tool. The trailer backup lamps should turn ON and OFF while changing between the commanded states. If the trailer backup lamps are always ON or always OFF, refer to Trailer Lamps Malfunction below.
  5. Observe the function of the trailer brake lamps while commanding the Trailer Brake Lamps ON and OFF with a scan tool. The trailer brake lamps should turn ON and OFF while changing between the commanded states. If the trailer brake lamps are always ON or always OFF, refer to Trailer Brake Lamps Malfunction below.
  6. If all trailer lamps are inoperative, refer to All Trailer Lamps Inoperative below.

Trailer Lamps Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the K67 trailer brake control module.
  2. Test for infinite resistance between the control circuit terminal listed below and ground: Right trailer turn signal lamp control terminal 2 Left trailer park lamp control terminal 4 Trailer backup lamp control terminal 7 Trailer fog lamp control terminal 8 Right trailer park lamp control terminal 16 Left trailer turn signal lamp control terminal 17 If not the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X88 trailer connector.
  3. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal listed below and ground: Right trailer turn signal lamp control terminal 2 Left trailer park lamp control terminal 4 Trailer backup lamp control terminal 7 Trailer fog lamp control terminal 8 Right trailer park lamp control terminal 16 Left trailer turn signal lamp control terminal 17 If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the X88 trailer connector.
  4. Test for less than 1 ohms between the control circuit terminals listed below: Right trailer turn signal lamp control terminal 2 at the K67 trailer brake control module and control terminal 4 at the X88 trailer connector. Left trailer park lamp control terminal 4 at the K67 trailer brake control module and control terminal 7 at the X88 trailer connector. Trailer backup lamp control terminal 7 at the K67 trailer brake control module and control terminal 8 at the X88 trailer connector. Trailer fog lamp control terminal 8 at the K67 trailer brake control module and control terminal 2 at the X88 trailer connector. Right trailer park lamp control terminal 16 at the K67 trailer brake control module and control terminal 5 at the X88 trailer connector. Left trailer turn signal lamp control terminal 17 at the K67 trailer brake control module and control terminal 1 at the X88 trailer connector. If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, replace the X88 trailer connector.
  5. If all circuits test normal, replace the K67 trailer brake control module.

Trailer Brake Lamps Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the K67 trailer brake control module.
  2. Connect a test lamp between the signal circuit terminal 14 and ground.
  3. Ignition ON, command the Center Brake Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF while changing between the commanded states. If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, refer to «Stop Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) . If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, refer to «Stop Lamps Malfunction»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) .
  4. Verify that a test lamp does not illuminate between the control circuit terminal 10 and ground. If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the X88 trailer connector.
  5. Test for infinite resistance between the control circuit terminal 10 and ground. If not the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X88 trailer connector.
  6. Test for less than 1 ohms between the control circuit 10 at the K67 trailer brake control module and the control circuit terminal 6 at the X88 trailer connector. If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, replace the X88 trailer connector.
  7. If all circuits test normal, replace the K67 trailer brake control module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for trailer brake control module replacement, programming setup

  1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/cadillac/srx/ii-2009-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Turn Signal Switch Signal222
Right Turn Signal Switch Signal333
Left Front Turn Signal Lamp ControlB3948 0244
Right Front Turn Signal Lamp ControlB3949 0255
Left Rear Turn Signal Lamp ControlB3950 0266
Right Rear Turn Signal Lamp ControlB3951 0277
Left Repeater Lamp ControlB3948 0288
Right Repeater Lamp ControlB3949 0299
Turn Signal/Multifunction Switch Ground1
Left Tail Lamp Ground6
Left Repeater Lamp Ground8
Right Repeater Lamp Ground9
Right Tail Lamp Ground7
1. All Turn Signals Lamps and/or Indicators Inoperative 2. Left Turn Signals Malfunction 3. Right Turn Signals Malfunction 4. Left Front Turn Signal Malfunction 5. Right Front Turn Signal Malfunction 6. Left Rear Turn Signal Malfunction 7. Right Rear Turn Signal Malfunction 8. Left Repeater Lamp Malfunction 9. Right Repeater Lamp Malfunction

Ground is applied at all times to the turn signal/multifunction switch. The turn signal lamps may only be activated with the ignition switch in the ON or START position. When the turn signal/multifunction switch is placed in either the TURN RIGHT or TURN LEFT position, ground is applied to the body control module through either the right turn or left turn signal switch signal circuit. The BCM then applies a pulsating voltage to the front and rear turn signal lamps through there respective voltage supply circuits. When a turn signal request is received by the BCM, a serial data message is sent to the instrument cluster requesting the respective turn signal indicator be pulsed ON and OFF.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures)
  4. «Wiring Repairs»(/cadillac/srx/ii-2009-2012/remont/body-electrical/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, observe the scan tool Left Turn Signal Switch parameter while moving the turn signal switch from the center position to the left position. The value should be Inactive and change to Active. If the value does not change, refer to Turn Signal Switch Malfunction below.
  2. Ignition ON, observe the scan tool Right Turn Signal Switch parameter while moving the turn signal switch from the center position to the right position. The value should be Inactive and change to Active. If the value does not change, refer to Turn Signal Switch Malfunction below.
  3. Ignition ON, with the turn signal switch in the left position, observe the function of the E4LF turn signal lamp-left front, the E4Y turn signal repeater lamp-left and the E4LR turn signal lamp-left rear. Each lamp should flash ON and OFF. If a lamp is always On or always OFF, refer to Turn Signal Lamps Malfunction below.
  4. Ignition ON, with the turn signal switch in the right position, observe the function of the E4RF turn signal lamp-right front, the E4Z turn signal repeater lamp-right and the E4RR turn signal lamp-right rear. Each lamp should flash ON and OFF. If a lamp is always ON or always OFF, refer to Turn Signal Lamps Malfunction below.
  5. Command the All Indicators Test ON and OFF with a scan tool. The left and right turn signal indicators should turn ON and OFF when changing between the commanded states. If the left and right turn signal indicators are always ON or always OFF, replace the P16 instrument cluster.

Turn Signal Switch Malfunction

  1. Ignition OFF, disconnect the X2 harness connector at the S78 turn signal/multi-function switch.
  2. Test for less than 30 ohms between the ground circuit terminal 3 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Left Turn Signal Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  4. Install a 3 A fused jumper wire between the signal circuit terminal 1 and ground. Verify the scan tool Left Turn Signal Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. Verify the scan tool Right Turn Signal Switch parameter is Inactive. If not the specified value, test the signal circuit terminal 7 for a short to ground. If the circuit tests normal, replace the K9 BCM.
  6. Install a 3 A fused jumper wire between the signal circuit terminal 7 and ground. Verify the scan tool Right Turn Signal Switch parameter is Active. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  7. If all circuits test normal, test or replace the S78 turn signal/multi-function switch.

Turn Signal Lamps Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate turn signal lamp.
  2. Test for less than 30 ohms between the ground circuit terminal listed below and ground. E4Y turn signal repeater lamp-left terminal 2 E4Z turn signal repeater lamp-right terminal 2 E4LR turn signal lamp-left rear terminal 1 E4RR turn signal lamp-right rear terminal 1 If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Disconnect the inline harness connector at the appropriate E4LF turn signal lamp-front listed below: E4LF turn signal lamp-left front X115 (Without TT6/TT7/TT8) E4LF turn signal lamp-left front X111 (With TT6/TT7/TT8) E4RF turn signal lamp-right front X116 (Without TT6/TT7/TT8) E4RF turn signal lamp-right front X112 (With TT6/TT7/TT8)
  4. Connect a test lamp between the control circuit terminal listed below and ground. E4LF turn signal lamp-left front terminal J E4RF turn signal lamp-right front terminal J E4Y turn signal repeater lamp-left terminal 1 E4LR turn signal lamp-left rear terminal 3 E4Z turn signal repeater lamp-right terminal 1 E4RR turn signal lamp-right rear terminal 3
  5. Command the appropriate Turn Signal Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. If all circuits test normal, replace the turn signal lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Turn Signal Multifunction Switch Replacement»(/cadillac/srx/ii-2009-2012/remont/steering-column-switches/#steering-wheel-and-steering-column)
  2. «Front Turn Signal Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Front Turn Signal Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system) or «Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system__front-turn-signal-lamp-bulb-replacement) or «Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  3. «Tail Lamp Replacement»(/cadillac/srx/ii-2009-2012/remont/exterior-lights/#lighting-system)
  4. «Control Module References»(/cadillac/srx/ii-2009-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM or instrument cluster replacement, setup and programming

Brake Pedal Position Sensor Calibration

Note. Brake system does not use a brake switch, stoplight switch or brakelight switch. System uses a Brake Pedal Position Sensor to control these functions.

Calibration Criteria

Note. Do not apply the brake pedal during the brake pedal position sensor calibration procedure. Any movement of the brake pedal during this procedure will cause the calibration procedure to fail. If this occurs, the brake pedal position sensor calibration must be repeated.

Brake pedal position sensor calibration must be performed after the brake pedal position sensor or body control module (BCM) have been serviced. The calibration procedure will set the brake pedal position sensor home value. This value is used by the BCM to determine the action of the driver applying the brake system and to provide this information to the vehicle subsystems via serial data.

Calibration Procedure

  1. Apply the parking brake.
  2. Place the transmission in the PARK position.
  3. Install a scan tool.
  4. Clear all BCM DTCs before proceeding.
  5. Navigate to the Module Diagnosis menu.
  6. Select BCM menu item.
  7. Select Configuration/Reset Functions menu item.
  8. Select the Brake Pedal Position Sensor Learn procedure and follow the directions displayed on the screen.

Brake Pedal Position Sensor Replacement

Note. Brake system does not use a brake switch, stoplight switch or brakelight switch. System uses a Brake Pedal Position Sensor to control these functions.

Scheme 18

Scheme 18: Brake Pedal Position Sensor Replacement
Scheme 18: Brake Pedal Position Sensor Replacement
CalloutComponent Name
Preliminary Procedure: Remove the instrument panel insulator panel. Refer to Instrument Panel Insulator Panel Replacement - Left Side .
1Brake Pedal Position Sensor Bolt CAUTION: Refer to Fastener Caution . Procedure: Remove the sensor bolt. Tighten: 9 N.m (80 lb in)
2Brake Pedal Position Sensor Procedure Disconnect the electrical connector. Pull the sensor away from the bracket. Recalibrate the brake pedal position sensor. Refer to Brake Pedal Position Sensor Calibration .
CAUTION
Refer to Fastener Caution .

Scheme 19

Scheme 19: Sun Load Temperature and Daytime Running Lamp Ambient Light Sensor Replacement
Scheme 19: Sun Load Temperature and Daytime Running Lamp Ambient Light Sensor Replacement
CalloutComponent Name
Preliminary Procedure: Remove the radio front speaker grille. Refer to Radio Front Speaker Grille Replacement .
1Sunload Temperature and Daytime Running Lamp and Ambient Light Sensor Procedure Twist and pull up to remove. Disconnect electrical connector.

Scheme 20

Scheme 20: Headlamp Switch Replacement
Scheme 20: Headlamp Switch Replacement
CalloutComponent Name
Preliminary Procedure: Remove instrument panel side trim panel. Refer to Instrument Panel Side Trim Panel Replacement .
1Headlamp Switch Procedure Depress tabs to remove the switch assembly from the instrument panel. Disconnect the electrical connector.

Scheme 21

Scheme 21: Trailer Lamp Control Module Replacement
Scheme 21: Trailer Lamp Control Module Replacement
CalloutComponent Name
Preliminary Procedure: Remove the rear compartment floor stowage compartment tray. Refer to Rear Compartment Floor Stowage Compartment Tray Replacement
1Rear Bracket Compartment Frame Nuts (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 9 N.m (80 lb in)
2Rear Bracket Compartment Frame Bolts (Qty: 2) Tighten: 9 N.m (80 lb in)
3Rear Bracket Compartment Frame
4Trailer Lamp Control Module Bolt Tighten: 9 N.m (80 lb in)
5Trailer Lamp Control Module Procedure Disconnect the electrical connector. Slide the module upward to remove. If installing a new trailer lamp control module, program the module. Refer to Control Module References .
CAUTION
Refer to Fastener Caution .

Scheme 22

Scheme 22: Reading Lamp Switch Push-button Replacement
Scheme 22: Reading Lamp Switch Push-button Replacement
CalloutComponent Name
Preliminary Procedure: Remove the roof console. Refer to Roof Console Replacement .
1Reading Lamp Switch Push-button Procedure: Press tabs together and remove switch.

Scheme 23

Scheme 23: Dome and Reading Lamp Switch Replacement
Scheme 23: Dome and Reading Lamp Switch Replacement
CalloutComponent Name
Preliminary Procedure: Remove the roof console. Refer to Roof Console Replacement .
1Dome and Reading Lamp Switch Disconnect the electrical connector. Release the tabs and remove the switch.

Scheme 24

Scheme 24: Dome Lamp Lens Replacement
Scheme 24: Dome Lamp Lens Replacement
CalloutComponent Name
1Dome Lamp Lens Procedure: Using nylon flat bladed tool release the four integral tabs on the lens from the roof console.

Scheme 25

Scheme 25: Instrument Panel Courtesy Lamp Replacement - Left Side
Scheme 25: Instrument Panel Courtesy Lamp Replacement - Left Side
CalloutComponent Name
1Instrument Panel Courtesy Lamp Procedure Use a plastic flat-bladed trim tool in order to release the lamp assembly from the drivers side insulator panel. Disconnect the electrical connection.
2Instrument Panel Courtesy Lamp Bulb

Scheme 26

Scheme 26: Instrument Panel Courtesy Lamp Replacement - Right Side
Scheme 26: Instrument Panel Courtesy Lamp Replacement - Right Side
CalloutComponent Name
1Instrument Panel Courtesy Lamp Procedure Use a plastic flat-bladed trim tool in order to release the lamp assembly from the instrument panel insulator panel. Disconnect the electrical connection.
2Instrument Panel Courtesy Lamp Bulb

Scheme 27

Scheme 27: Front Floor Console Flood Lamp Replacement
Scheme 27: Front Floor Console Flood Lamp Replacement
CalloutComponent Name
Preliminary Procedure: Remove the roof console. Refer to Roof Console Replacement .
1Front Floor Console Flood Lamp Procedure: Disconnect electrical connector.

Scheme 28

Scheme 28: Rear Side Door Courtesy Lamp Replacement
Scheme 28: Rear Side Door Courtesy Lamp Replacement
CalloutComponent Name
1Rear Side Door Courtesy Lamp Procedure Depress the clips and use a flat-bladed tool to remove the door courtesy lamp from the door trim panel. Disconnect the electrical connectors.
2Rear Side Door Courtesy Lamp Bulb

Scheme 29

Scheme 29: Front Side Door Courtesy Lamp Replacement
Scheme 29: Front Side Door Courtesy Lamp Replacement
CalloutComponent Name
1Front Side Door Courtesy Lamp Procedure Depress the clips and use a flat-bladed tool to remove the door courtesy lamp from the door trim panel. Disconnect the electrical connectors.
2Front Side Door Courtesy Lamp Bulb

Scheme 30

Scheme 30: Front Side Door Warning Lamp Replacement
Scheme 30: Front Side Door Warning Lamp Replacement
CalloutComponent Name
Preliminary Procedure: Remove the front side door trim panel. Refer to Front Side Door Trim Replacement
1Front Side Door Applique Refer to Front Side Door Trim Panel Finish Panel Applique Replacement .
2Front Side Door Warning Lamp Procedure: Disconnect the electrical connector.

Scheme 31

Scheme 31: Rear Side Door Warning Lamp Replacement
Scheme 31: Rear Side Door Warning Lamp Replacement
CalloutComponent Name
Preliminary Procedure Remove the rear side door trim panel. Refer to Rear Side Door Trim Replacement Disconnect the warning lamp connector.
1Rear Side Door Applique Refer to Rear Side Door Trim Panel Applique Replacement .
2Rear Side Door Warning Lamp Procedure: After the lamp has been disconnected, gently pull connector through opening and remove lamp from integral clips.

Scheme 32

Scheme 32: Instrument Panel Flood Lamp Replacement - Left Side
Scheme 32: Instrument Panel Flood Lamp Replacement - Left Side
CalloutComponent Name
Preliminary Procedure: Remove the instrument panel accessory switch trim panel - left side. Refer to Instrument Panel Accessory Switch Trim Panel Replacement - Left Side
1Instrument Panel Flood Lamp Procedure: Unsnap the flood lamp assembly from instrument panel accessory switch trim panel.

Scheme 33

Scheme 33: Instrument Panel Flood Lamp Replacement - Right Side
Scheme 33: Instrument Panel Flood Lamp Replacement - Right Side
CalloutComponent Name
Preliminary Procedure: Remove the instrument panel trim panel. Refer to Instrument Panel Trim Panel Replacement
1Instrument Panel Flood Lamp Procedure Note the routing of the wiring through the instrument panel assembly to ensure proper reinstallation. Disconnect the electrical connector. Unsnap the flood lamp assembly from the instrument panel trim.

Scheme 34

Scheme 34: Front Seat Back Courtesy Lamp Replacement
Scheme 34: Front Seat Back Courtesy Lamp Replacement
CalloutComponent Name
1Front Seat Back Courtesy Lamp Procedure Disconnect the electrical connector. Squeeze the bottom tabs together and push up to remove.

Scheme 35

Scheme 35: Instrument Panel Compartment Lamp Replacement
Scheme 35: Instrument Panel Compartment Lamp Replacement
CalloutComponent Name
1Instrument Panel Compartment Lamp Procedure Use a plastic flat bladed trim tool in order to release the lamp assembly from the instrument panel compartment housing. Disconnect the electrical connection.

Scheme 36

Scheme 36: Instrument Panel Compartment Lamp Bulb Replacement
Scheme 36: Instrument Panel Compartment Lamp Bulb Replacement
CalloutComponent Name
Preliminary Procedure: Remove the instrument panel compartment lamp. Refer to Instrument Panel Compartment Lamp Replacement .
1Instrument Panel Compartment Lamp Bulb

Scheme 37

Scheme 37: Roof Rail Courtesy and Reading Lamp Replacement
Scheme 37: Roof Rail Courtesy and Reading Lamp Replacement
CalloutComponent Name
Preliminary Procedure: Remove the roof rail rear assist handle. Refer to Roof Rail Rear Assist Handle Replacement .
1Roof Rail Courtesy and Reading Lamp Assembly
2Roof Rail Courtesy and Reading Lamp Lens Procedure: From the backside of the lamp assembly, using the appropriate tool, depress tab on indented side and then disengage the opposite side of the lens.
3Light Plate Blocker Bolt CAUTION: Refer to Fastener Caution . Tighten: 2.5 N.m (22 lb in)
4Light Plate Blocker Tip: Remove blocker, if equipped.
5Roof Rail Courtesy and Reading Lamp Bulb
6Roof Rail Courtesy and Reading Lamp Bezel Tip: Remove any protective films from service part.
CAUTION
Refer to Fastener Caution .

Scheme 38

Scheme 38: Sunshade Illuminated Mirror Lamp Bulb Replacement
Scheme 38: Sunshade Illuminated Mirror Lamp Bulb Replacement
CalloutComponent Name
Preliminary Procedure: Remove the sunshade illuminated mirror lamp lens. Refer to Sunshade Illuminated Mirror Lamp Lens Replacement
1Sunshade Illuminated Mirror Lamp Bulb

Scheme 39

Scheme 39: Sunshade Illuminated Mirror Lamp Lens Replacement
Scheme 39: Sunshade Illuminated Mirror Lamp Lens Replacement
CalloutComponent Name
1Sunshade Illuminated Mirror Lamp Lens Procedure: Carefully use a flat bladed tool, and release the tabs retaining the lamp lens to the sunshade assembly.

Scheme 40

Scheme 40: Dome Lamp Bulb Replacement
Scheme 40: Dome Lamp Bulb Replacement
CalloutComponent Name
Preliminary Procedure: Remove the dome lamp lens. Refer to Dome Lamp Lens Replacement .
1Dome Lamp Bulb

Scheme 41

Scheme 41: Headlamp Replacement
Scheme 41: Headlamp Replacement
CalloutComponent Name
Preliminary Procedure Open and support the hood. Remove the front bumper fascia. Refer to Front Bumper Fascia Replacement . Remove the front compartment side sight shields. Refer to Front Compartment Side Sight Shield Replacement . Disconnect the headlamp electrical connector at the base of the headlamp assembly.
1Headlamp Assembly Screw (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 6 N.m (53 lb in)
2Headlamp Assembly WARNING: Refer to Halogen Bulb Warning . Procedure Remove both accessory bulb covers and transfer. Disconnect the electrical connectors from the headlamp bulbs. Remove the low beam bulb and transfer. Remove the high beam bulb and transfer. Disengage the park turn signal bulb socket and transfer the bulb.
CAUTION
Refer to Fastener Caution .
WARNING
Refer to Halogen Bulb Warning .

Scheme 42

Scheme 42: Headlamp Bulb Replacement - Left Side (T84, T85)
Scheme 42: Headlamp Bulb Replacement - Left Side (T84, T85)
CalloutComponent Name
Preliminary Procedure Remove the under electrical center (UEC) cover. Disengage the three locking tabs from the cover and remove.
1Headlamp Bulb Accessory Cover Procedure: Rotate the cover counter-clockwise and remove. Tip: Notice the direction of the arrow on the cover, ensure the arrow points downward upon re-installing the cover.
2Headlamp Bulb (High Beam) WARNING: Refer to Halogen Bulb Warning . Procedure Disconnect the electrical connector prior to removing the headlamp bulb from the headlamp assembly. Rotate the bulb socket counter-clockwise and remove.
WARNING
Refer to Halogen Bulb Warning .

Scheme 43

Scheme 43: Headlamp Bulb Replacement - Right Side (T84, T85)
Scheme 43: Headlamp Bulb Replacement - Right Side (T84, T85)
CalloutComponent Name
Preliminary Procedure: Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LF1) or Air Cleaner Assembly Replacement (LAU) .
1Headlamp Bulb Accessory Cover Procedure: Rotate the cover counter-clockwise and remove. Tip: Note the direction of the arrow on the cover, ensue the arrow points downward upon re-installing the cover to the headlamp.
2Headlamp Bulb Electrical Connector Tip: Disconnect prior to removing the headlamp bulb from the headlamp housing.
3Headlamp Bulb (High Beam) WARNING: Refer to Halogen Bulb Warning . Procedure: Rotate the bulb socket counter-clockwise and remove.
WARNING
Refer to Halogen Bulb Warning .

Scheme 44

Scheme 44: Headlamp Ballast Replacement (TT6, TT7, TT8)
Scheme 44: Headlamp Ballast Replacement (TT6, TT7, TT8)
CalloutComponent Name
WARNING: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. WARNING: The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system. Preliminary Procedure: Remove the headlamp capsule. Refer to Headlamp Capsule Replacement (TT6, TT7, TT8) .
1Headlamp Ballast Screw (Qty: 3) Tip: Hand tighten the ballast screws.
2Headlamp Ballast Tip: Ensure the ballast seal is properly seated onto the ballast prior to installing the ballast to the headlamp capsule.
WARNING
The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
WARNING
The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system.

Scheme 45

Scheme 45: Headlamp Ignitor Replacement (TT6, TT7, TT8 Passenger Side)
Scheme 45: Headlamp Ignitor Replacement (TT6, TT7, TT8 Passenger Side)
CalloutComponent Name
WARNING: The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system. WARNING: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. Preliminary Procedure: Remove the headlamp ballast. Refer to Headlamp Ballast Replacement (TT6, TT7, TT8) .
1Headlamp Bulb Accessory Cover Procedure: Rotate the cover counter-clockwise a quarter turn and remove from the headlamp capsule.
2Headlamp Ignitor Assembly WARNING: Refer to Halogen Bulb Warning . Procedure Release the retention spring in order to remove the high intensity discharge (HID) ignitor bulb. Disconnect the electrical connector. Rotate the ignitor bulb and remove.
WARNING
The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system.
WARNING
The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
WARNING
Refer to Halogen Bulb Warning .

Scheme 46

Scheme 46: Headlamp Ignitor Replacement (TT6, TT7, TT8 Driver Side)
Scheme 46: Headlamp Ignitor Replacement (TT6, TT7, TT8 Driver Side)
CalloutComponent Name
WARNING: The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system. WARNING: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. Preliminary Procedure: Remove the headlamp ballast. Refer to Headlamp Ballast Replacement (TT6, TT7, TT8) .
1Headlamp Bulb Accessory Cover Procedure: Rotate the cover counter-clockwise a quarter turn and remove from the headlamp capsule.
2Headlamp Ignitor Assembly WARNING: Refer to Halogen Bulb Warning . Procedure Release the retention spring in order to remove the high intensity discharge (HID) ignitor bulb. Disconnect the electrical connector. Rotate the ignitor bulb and remove.
WARNING
The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system.
WARNING
The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
WARNING
Refer to Halogen Bulb Warning .

Headlamp Capsule Replacement (TT6, TT7, TT8)

CalloutComponent Name
WARNING: The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system. WARNING: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. Preliminary Procedure Open and support the hood. Remove the front bumper fascia. Refer to Front Bumper Fascia Replacement . Remove the front compartment side sight shields. Refer to Front Compartment Side Sight Shield Replacement . Disconnect the headlamp electrical connector at the base of the headlamp assembly.
1Headlamp Assembly Screw (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 6 N.m (53 lb in)
2Headlamp Capsule Assembly WARNING: Refer to Halogen Bulb Warning . Procedure Carefully move the headlamp capsule assembly upward and outward in order to remove. Remove and transfer both headlamp bulb accessory covers and gaskets. Disconnect the electrical connectors. Remove and transfer the headlamp ignitor bulb. Remove and transfer the daytime running lamp (DRL) bulb. Disengage the park turn signal lamp socket. Remove and transfer the park turn signal lamp bulb.
WARNING
The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system.
WARNING
The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
CAUTION
Refer to Fastener Caution .
WARNING
Refer to Halogen Bulb Warning .

Headlamp Aiming

The vehicle has a visual optical headlamp aiming system. The headlamp aiming system has been preset at the factory.

However, If the vehicle is damaged in an accident, the aim of the headlamps can be affected and adjustment could be necessary.

The vehicle should be properly prepared as follows

  1. The vehicle should be placed so the headlamps are 25 ft (7.6 m) from a light colored wall or other flat surface.
  2. The vehicle must have all four tires on a perfectly level surface which is level all the way to the wall or other flat surface.
  3. The vehicle should be placed so it is perpendicular to the wall or other flat surface.
  4. The vehicle should not have any snow, ice or mud on it.
  5. The vehicle should be fully assembled and all other work stopped while headlamp aiming is being done.
  6. The vehicle should be normally loaded with a full tank of fuel and one person or 160 lbs (75 kg) on the driver seat.
  7. Tires should be properly inflated.

Headlamp aiming is done with the vehicle low-beam headlamps. The high-beam headlamps will be correctly aimed if the low-beam headlamps are aimed properly.

  1. To adjust the vertical aim
  2. Locate the aim point at the center inner projector condensing lens of the low beam headlamp (not the outer lens).
  3. Measure the distance from the ground to the aim dot on the low beam headlamp.
  4. Record the distance.
  5. At the wall, measure from the ground upward to the recorded distance from step 3, and draw or tape a horizontal line (3) the width of the vehicle.
  6. Turn on the low-beam headlamps and place a piece of cardboard or equivalent in front of the headlamp not being adjusted. This only allows the beam of light from the headlamp being adjusted to be seen on the flat surface.
  7. Locate the vertical aiming screws, which are under the hood near each headlamp assembly.
  8. For the vehicle that is equipped with a Base headlamp (halogen bulb), there will be one vertical headlamp aiming screw (V1).
  9. The aiming screw (V1) is adjusted from the engine compartment side of the beauty cover.
  10. For the vehicle that is equipped with an Up-level headlamp (HID), there will be two vertical headlamp aiming screws (V1 and V2).
  11. The aiming screw (V1) is adjusted from the engine compartment side of the beauty cover and the aiming screw (V2) is adjusted through the access hole in the beauty cover.
  12. For the Base vehicle, turn the vertical aiming screw (V1) until the headlamp beam is aimed to the horizontal tape line. Turn it clockwise or counter-clockwise to raise or lower the angle of the beam.
  13. For the Up-level vehicle, turn the vertical aiming screws (V1 and V2) simultaneously until the headlamp beam is aimed to the horizontal tape line. Turn them clockwise or counter-clockwise to raise or lower the angle of the beam.
  14. Make sure that the light from the headlamp is positioned at the bottom edge (1,2) of the horizontal tape line (3).
  15. Repeat steps 7 through 14 for the opposite headlamp.

Scheme 47

Scheme 47: Headlamp Leveling Front Suspension Height Sensor Replacement
Scheme 47: Headlamp Leveling Front Suspension Height Sensor Replacement
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the left front wheel and tire assembly. Refer to Tire and Wheel Removal and Installation . Disconnect the headlamp leveling front suspension height sensor electrical connector.
1Headlamp Leveling Front Suspension Height Sensor Socket Procedure: Disconnect the headlamp leveling front suspension height sensor socket from the ball stud.
2Headlamp Leveling Front Suspension Height Sensor Fastener CAUTION: Refer to Fastener Caution . Tighten: 8 N.m (71 lb in)
3Headlamp Leveling Front Suspension Height Sensor
CAUTION
Refer to Fastener Caution .

Scheme 48

Scheme 48: Headlamp Leveling Rear Suspension Height Sensor Replacement
Scheme 48: Headlamp Leveling Rear Suspension Height Sensor Replacement
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Disconnect the headlamp leveling suspension height sensor electrical connector.
1Headlamp Leveling Rear Suspension Height Sensor Socket Procedure: Disconnect the headlamp leveling rear suspension height sensor socket from the ball stud.
2Headlamp Leveling Rear Suspension Height Sensor Fastener CAUTION: Refer to Fastener Caution . Tighten: 8 N.m (71 lb in)
3Headlamp Leveling Rear Suspension Height Sensor
CAUTION
Refer to Fastener Caution .

Scheme 49

Scheme 49: Headlamp Control Module Replacement
Scheme 49: Headlamp Control Module Replacement
CalloutComponent Name
Preliminary Procedure: Remove the body control module. Refer to Body Control Module Replacement and mounting bracket.
1Headlamp Control Module Nuts (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 6 N.m (53 lb in)
2Headlamp Control Module Procedure Disconnect the electrical connectors. Refer to Control Module References for programming and set up procedures.
CAUTION
Refer to Fastener Caution .

Scheme 50

Scheme 50: Front Fog Lamp Replacement
Scheme 50: Front Fog Lamp Replacement
CalloutComponent Name
Preliminary Procedures Remove either the LF or RF wheelhouse liner. Refer to Front Wheelhouse Liner Replacement . Disconnect the fog lamp bulb socket electrical connector.
1Front Fog Lamp Adjuster Screw
2Front Fog Lamp Screw (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 2.5 N.m (22 lb in)
3Front Fog Lamp Assembly Procedure: Aim the fog lamps after installation. Refer to Fog Lamp Aiming .
4Front Fog Lamp Bulb Socket WARNING: Refer to Halogen Bulb Warning . Tip: Turn the bulb socket counterclockwise and remove from the lamp assembly.
CAUTION
Refer to Fastener Caution .
WARNING
Refer to Halogen Bulb Warning .

Adjustment Procedure

Proper road illumination and safety require the fog lamps to be aimed. The front fog lamp aim should be checked when a new front fog lamp assembly is installed, or if any service repairs have been performed to the vehicle which disturb the front fog lamp mounting or the vehicle ride height.

There are no horizontal adjustments for aiming the front fog lamp assemblies on this vehicle.

  1. To ensure accurate vertical front fog lamp aiming, first perform the following steps to prepare the vehicle. Make sure that all the components are in place on the vehicle, the tires are properly inflated, and there is not any mud or snow clinging to the vehicle. Stop all other operations of work on the vehicle. Make sure the fuel level is 1/2 full or more. Jounce the vehicle to settle the suspension. Place the vehicle on a level surface 7.6 m (25 ft) from the target screen. Measure the distance from the floor to the center of the fog lamp (5). Using this measurement, mark the horizontal centerline of the fog lamp (1) on the target screen directly in front of the vehicle. Start the vehicle in order to level the suspension.
  2. Turn the front fog lamps ON.
  3. Adjust (1) the fog lamp up or down until the top edge of the high intensity zone on the screen is 102 mm (4 in) below the horizontal centerline (1).
  4. Turn OFF the front fog lamps.

Scheme 51

Scheme 51: Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)
Scheme 51: Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)
CalloutComponent Name
WARNING: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. WARNING: The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system. Preliminary Procedure: Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LF1) or Air Cleaner Assembly Replacement (LAU) .
1Headlamp Bulb Accessory Cover Tip: Rotate the cover counter-clockwise and remove.
2Daytime Running Lamp Bulb Socket WARNING: Refer to Halogen Bulb Warning . Procedure: Rotate the bulb socket counter-clockwise and remove.
3Daytime Running Lamp Bulb Tip: Pull the bulb from the socket and replace.
WARNING
The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
WARNING
The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system.
WARNING
Refer to Halogen Bulb Warning .

Scheme 52

Scheme 52: Daytime Running Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)
Scheme 52: Daytime Running Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)
CalloutComponent Name
Preliminary Procedure: Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LF1) or Air Cleaner Assembly Replacement (LAU) .
1Headlamp Bulb Accessory Cover Tip: Rotate the cover counter-clockwise and remove.
2Daytime Running Lam/Low Beam Headlamp Bulb WARNING: Refer to Halogen Bulb Warning . Tip: Disconnect prior to removing the headlamp bulb from the headlamp housing. Procedure: Rotate the bulb socket counter-clockwise and remove.
WARNING
Refer to Halogen Bulb Warning .

Scheme 53

Scheme 53: Daytime Running Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)
Scheme 53: Daytime Running Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)
CalloutComponent Name
Preliminary Procedure Remove the under electrical center (UEC) cover. Disengage the three locking tabs from the cover and remove.
1Headlamp Bulb Accessory Cover Tip: Rotate the cover counter-clockwise and remove.
2Daytime Running Lamp/Low Beam Headlamp Bulb WARNING: Refer to Halogen Bulb Warning . Tip: Disconnect the electrical connector prior to removing the headlamp bulb from the headlamp housing. Procedure: Rotate the bulb socket counter-clockwise and remove.
WARNING
Refer to Halogen Bulb Warning .

Scheme 54

Scheme 54: Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)
Scheme 54: Daytime Running Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)
CalloutComponent Name
Preliminary Procedure WARNING: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. WARNING: The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system. Remove the underhood electrical center (UEC) cover. Disengage the three locking tabs and remove the cover.
1Headlamp Bulb Accessory Cover Procedure: Rotate the cover counter-clockwise and remove. Tip: Ensure the arrow on the cover is pointing downward upon re-installation of the cover to the headlamp capsule.
2Daytime Running Lamp (DRL) Bulb Socket WARNING: Refer to Halogen Bulb Warning . Procedure: Rotate the bulb socket counter-clockwise and remove.
3Daytime Running Lamp (DRL) Bulb Tip: Pull the bulb from the socket and replace.
WARNING
The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
WARNING
The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system.
WARNING
Refer to Halogen Bulb Warning .

Scheme 55

Scheme 55: Front Side Turn Signal Lamp Replacement
Scheme 55: Front Side Turn Signal Lamp Replacement
CalloutComponent Name
1Side Turn Signal Lamp Assembly Procedure Remove the front wheelhouse liner in order to access the fasteners for the front turn signal lamp. Refer to Front Wheelhouse Liner Replacement . Begin releasing the retainers at the bottom of the side turn signal lamp and work towards the top. When the first lower retainer clip is released, insert a small plastic flat-bladed tool between the exterior body panel and the side turn signal assembly to prevent the retainer from re-engaging back into the fender panel hole. Disconnect the electrical harness connector from the side turn signal lamp housing. Connect the electrical harness lamp socket to the side turn signal lamp housing. Position the side turn signal lamp retainers to the fender holes. Using the palm portion of the hand, secure the retainers to the fender holes. An light audible click will be heard when each retainer is secure to the fender panel.
2Front Side Turn Signal Lamp Bulb Socket

Scheme 56

Scheme 56: Front Side Turn Signal Lamp Bulb Replacement
Scheme 56: Front Side Turn Signal Lamp Bulb Replacement
CalloutComponent Name
Preliminary Procedures Remove the front wheelhouse liner. Refer to Front Wheelhouse Liner Replacement . Reach inside the fender well and rotate the bulb socket a quarter turn and remove. Pull the turn signal lamp bulb from the lamp socket.
1Front Side Turn Signal Lamp Socket Tip: Ensure the fingers on the turn signal lamp socket point forward upon installation. If the socket fingers point rearward, the bulb socket will not seal in the lamp housing.
2Front Side Turn Signal Lamp Bulb

Scheme 57

Scheme 57: Front Turn Signal Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)
Scheme 57: Front Turn Signal Lamp Bulb Replacement (T84, T85 Driver Side Headlamp)
CalloutComponent Name
Preliminary Procedure Remove the under electrical center (UEC) cover. Disengage the three locking tabs from the cover and remove.
1Park Turn Signal Bulb Socket Procedure: Rotate the park turn bulb socket counter-clockwise and remove.
2Park Turn Signal Bulb WARNING: Refer to Halogen Bulb Warning . Procedure: Pull the bulb from the park turn signal bulb socket and replace.
WARNING
Refer to Halogen Bulb Warning .

Scheme 58

Scheme 58: Front Turn Signal Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)
Scheme 58: Front Turn Signal Lamp Bulb Replacement (T84, T85 Passenger Side Headlamp)
CalloutComponent Name
Preliminary Procedure: Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LF1) or Air Cleaner Assembly Replacement (LAU) .
1Park Turn Signal Bulb Socket Procedure: Rotate the park turn signal bulb socket counter-clockwise and remove.
2Park Turn Signal Bulb WARNING: Refer to Halogen Bulb Warning . Procedure: Pull the park turn signal bulb from the socket and replace.
WARNING
Refer to Halogen Bulb Warning .

Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)

CalloutComponent Name
Preliminary Procedure: WARNING: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. WARNING: The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement (LF1) or Air Cleaner Assembly Replacement (LAU) .
1Headlamp Bulb Access Cover
2Park Turn Signal Bulb Socket Procedure: Rotate the park turn signal bulb socket counter-clockwise and remove.
3Park Turn Signal Bulb WARNING: Refer to Halogen Bulb Warning . Procedure: Pull the park turn signal bulb from the bulb socket and replace.
WARNING
The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
WARNING
The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system.
WARNING
Refer to Halogen Bulb Warning .

Scheme 59

Scheme 59: Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)
Scheme 59: Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Driver Side Headlamp)
CalloutComponent Name
Preliminary Procedure WARNING: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. WARNING: The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system. Remove the underhood electrical center (UEC) cover. Disengage the three locking tabs and remove the cover.
1Park Turn Signal Bulb Socket WARNING: Refer to Halogen Bulb Warning . Procedure: Rotate the bulb socket counter-clockwise and remove.
2Park Turn Signal Bulb Tip: Pull the bulb from the socket and replace.
WARNING
The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.
WARNING
The high intensity discharge system produces high voltage and current. In order to reduce the risk of severe shocks and burns, the battery negative cable must be disconnected any time service work is being performed on or around the high intensity discharge system.
WARNING
Refer to Halogen Bulb Warning .

Scheme 60

Scheme 60: High Mount Stop Lamp Replacement
Scheme 60: High Mount Stop Lamp Replacement
CalloutComponent Name
Preliminary Procedures Open the liftgate. Remove the rear End spoiler. Refer to Rear End Spoiler Replacement . Place the rear spoiler on a clean protected surface in order to remove the Light Emitted Diode (LED) high mounted stop lamp.
1High Mount Stop Lamp Screw (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 2 N.m (18 lb in)
2High Mount Stop Lamp Assembly Procedure: Remove the high mount (LED) stop lamp from the back side of the rear spoiler.
CAUTION
Refer to Fastener Caution .

Scheme 61

Scheme 61: Backup Lamp Bulb Replacement
Scheme 61: Backup Lamp Bulb Replacement
CalloutComponent Name
Preliminary Procedure: Remove the rear tail lamp assembly. Refer to Tail Lamp Replacement .
1Back Up Lamp Bulb WARNING: Refer to Halogen Bulb Warning . Procedure: Rotate the back up lamp bulb socket counterclockwise from the tail lamp assembly.
WARNING
Refer to Halogen Bulb Warning .

Scheme 62

Scheme 62: Tail Lamp Replacement
Scheme 62: Tail Lamp Replacement
CalloutComponent Name
Preliminary Procedure: Open the rear liftgate in order to access and remove the tail lamp screws.
1Tail Lamp Filler Panel Procedure: Using a suitable flat bladed tool, remove the push-pin and tail lamp filler panel.
2Tail Lamp Screw (Qty 2) CAUTION: Refer to Fastener Caution . Tighten: 2.5 N.m (22 lb in)
3Tail Lamp Assembly Procedure Pull on the outer edge of the tail lamp assembly in order to release the tail lamp locator pins from the rear bodyside panel. Disconnect the electrical connectors.
CAUTION
Refer to Fastener Caution .

Scheme 63

Scheme 63: Rear Turn Signal Lamp Bulb Replacement
Scheme 63: Rear Turn Signal Lamp Bulb Replacement
CalloutComponent Name
Preliminary Procedure: Remove the rear tail lamp assembly. Refer to Tail Lamp Replacement .
1Rear Turn Signal Bulb WARNING: Refer to Halogen Bulb Warning . Procedure: Rotate the rear turn signal lamp bulb socket counterclockwise from the tail lamp assembly.
WARNING
Refer to Halogen Bulb Warning .

Scheme 64

Scheme 64: Rear Compartment Courtesy Lamp Replacement - Liftgate
Scheme 64: Rear Compartment Courtesy Lamp Replacement - Liftgate
CalloutComponent Name
1Rear Compartment Courtesy Lamp - Liftgate Procedure Use a plastic flat bladed trim tool in order to release the lamp assembly from the liftgate trim panel. Disconnect the electrical connection.
2Rear Compartment Courtesy Lamp Bulb

Scheme 65

Scheme 65: Rear Compartment Courtesy Lamp Replacement - Quarter Upper Trim
Scheme 65: Rear Compartment Courtesy Lamp Replacement - Quarter Upper Trim
CalloutComponent Name
1Rear Compartment Courtesy Lamp - Quarter Upper Trim Procedure Use a plastic flat bladed trim tool in order to release the lamp assembly from the rear quarter trim panel. Disconnect the electrical connection.
2Rear Compartment Courtesy Lamp Bulb

Exterior Lamps

The exterior lighting system consist of the following lamps

  1. Automatic headlamp leveling
  2. Headlamps
  3. Adaptive forward lighting
  4. Daytime running lamps (DRL)
  5. Front fog lamps
  6. Rear fog lamps
  7. Park, tail, license and marker lamps
  8. Turn signal lamps
  9. Hazard warning lamps
  10. Repeater lamps
  11. Stop lamps
  12. Backup lamps
  13. Position lamps

Low Beam Headlamps (Standard) RPO TT4

The headlamps consist of 2 interchangeable single filament bulbs or 2 high intensity discharge (HID) arc tubes and ballast on each side of the vehicle which provide high and low beams. The lower bulb in the headlamp is the high beam and the upper bulb is the low beam.

The headlamps may be turned ON in 3 different ways

  1. When the headlamp switch is placed in the ON position, for normal operation
  2. When the headlamp switch is placed in the AUTOMATIC LIGHT position, for automatic lamp control
  3. When the headlamp switch is placed in the AUTOMATIC LIGHT position, with the windshield wipers ON in daylight conditions, after a 6 s delay

The body control module (BCM) controls the headlamps based on the inputs explained above. When a low beam request is received, the BCM supplies B+ to both low beam headlamps, illuminating the low beam headlamps.

When a high beam request is received, the BCM grounds the headlamp high beam relay control circuit. This energizes the coil in the headlamp high beam relay, causing the relay switch to close. This then applies B+ to both high beam headlamps through the left high beam and right high beam fuses, illuminating the high beam headlamps.

High Intensity Discharge (HID) Low Beam Headlamps (up level) RPO TT6

The BCM controls the headlamps based on the inputs explained above. When a low beam request is received, the BCM grounds the headlamp low beam relay control circuit. This energizes the coil in the headlamp low beam relay, causing the relay switch to close. This then applies B+ to both low beam HID headlamps through the left low beam and right low beam fuses, illuminating the low beam headlamps. When a high beam request is received, the BCM grounds the headlamp high beam relay control circuit. This energizes the coil in the high beam relay, causing the relay switch to close. This then applies B+ to both low beam HID headlamps through the left high beam and right high beam fuses which results in lifting the shutter of both headlamps. This causes the Xenon lamp to illuminate the headlamp at full brightness.

Run Up Of The Lamp

Each ballast requires higher amperage in order to ensure normal startup and run up of the lamp. Run up is the term used to describe the extra power level given to the bulb. The input current during the steady state operation is lower that the start up amperage. After the lamp receives the strike from the starter and the arc is established, the ballast uses its operating voltage in order to provide the run up power needed in order to keep the lamp ON. The lamp rapidly increases in intensity from a dim glow to a very high-intensity, bright light called a steady state. Within a few seconds of the arc being established in the bulb, the majority of steady state is complete. 100 percent of the steady state is completed shortly there after. A high watt power level is necessary in order to bring the lamp to a steady state in such a short period of time. The high watt power level allows the lamp to meet the SAE light vs. time specification.

When To Change The HID Bulb

An inoperative bulb, end of life occurs when the bulb gets old and becomes unstable. The bulb may begin shutting itself OFF sporadically and unpredictably at first, perhaps only once during a 24 h period. When the bulb begins shutting itself off occasionally, the ballast will automatically turn the bulb back ON again within 0.5 s. The ballast will restrike the bulb so quickly that the bulb may not appear to have shut off. As the bulb ages, the bulb may begin to shut off more frequently, eventually over 30 times per minute. When the bulb begins to shut off more frequently, the ballast receives an extreme amount of repetitive current input. Repetitive and extreme amount restarts or restrikes, without time for the ballast to cool down, will permanently damage the ballast. As a safeguard, when repetitive restrikes are detected, the ballast will not attempt to restrike the lamp. The ballast then shuts down and the bulb goes out.

The following symptoms are noticeable signs of an inoperative bulb

  1. Flickering light, caused in the early stages of an inoperative bulb
  2. Lights go out, caused when the ballast detects, repetitive bulb restrike
  3. Color change - The lamp may change to a dim pink glow.

Input power to the ballast must be terminated in order to reset the ballasts fault circuitry. In order to terminate the input power to the ballast, turn the lights OFF and back ON again. Turning the lights OFF and back ON again resets all of the fault circuitry within the ballast until the next occurrence of an extreme amount of repetitive bulb restrike. When an extreme amount of repetitive bulb restrikes occur, replace the starter/arc tube assembly. The ballast will begin the start-up process when the starter/arc tube assembly is replaced. Repeatedly resetting the input power can overheat the internal components and cause permanent damage to the ballast. Allow a few minutes of cool-down time in between reset attempts.

Inoperative bulbs are often sporadic at first, and difficult to repeat. Inoperative bulbs can be identified by observing if the condition gets progressively worse over the next 100 h of operation.

Light Color

White light has a different color rating than regular headlamps. The range of white light that is acceptable is broad when compared to halogens. Therefore, some variation in headlight coloring between the right and left headlamp will be normal. One HID at the end of the normal range may appear considerably different in color from one at the other end of the range. Difference in color is normal. Replace the arc tube only if the arc tube is determined to be at the bulb inoperative stage.

Adaptive Forward Lighting

The adaptive forward lighting consist of the following components

  1. Headlamp control module
  2. Headlamp actuator - left
  3. Headlamp actuator - right

Dynamic Curve Light

Bend lighting is a function depending on the following signal input values

  1. Steering angle
  2. Vehicle speed
  3. Yaw Rate

The appropriate swivel angle is calculated based on vehicle speed and the steering angle value.

Town Light

Town Light is activated while the vehicle speed is below 55 km/h (34 MPH) as well as the light sensor detects street lights and the town road category is detected. The light distribution is reduced to an area near the car due to low speeds.

Motorway Light

If vehicle speed is above 100 km/h (62 MPH) for at least 20 s (or once above 126 km/h (78 MPH)) and the corresponding road category is identified, the headlamps will be switched to a motorway light distribution. During motorway light the light output of the HID bulb is increased to 38 W by electrical power management. This improves the visibility range at the far end of the road.

Country Light

Country light replaces the current low beam and will be controlled based on programmable vehicle thresholds as well as corresponding road detection. The vehicle speed has to be between 55 km/h (34 MPH) and 100 km/h (62 MPH). Country light is the default light distribution at 35 W. Light distribution is reduced on the left side to prevent oncoming traffic from being dazzled.

Tourist Mode with RPO TT7 and TT8

The tourist mode functionality switches the adaptive forward lighting headlamps into a non dazzling mode, if the traffic regulation moves from left hand traffic to right hand traffic and vice versa. The functionality is switched on/off with the same stalk/switch combination. The "flash to pass" stalk needs to be activated while ignition is switched on (System Power Mode = RUN). The "flash to pass" stalk remains activated until the warning indicator within the instrument panel cluster starts flashing (4 s) and an acoustic indication is sent. The activation period takes about 3 s. An activation flag must be set within the adaptive forward lighting ECM and stored in non-volatile memory. Each time the ignition is switched on and the tourist mode is active, the warning indicator is flashing about 4 s. The tourist mode is deactivated with the same procedure described above. The function is switched OFF, if an acoustic signal is sent (Warning indicator remains inactive).

Adverse Weather Light

Adverse weather light will be switched on while the vehicle speed is below 100 km/h (62 MPH) and the windscreen wipers are activated. The HID bulbs will be powered with different values

  1. left: 32 W
  2. right: 38 W

The main advantage is that reflections on the wet floor are reduced to a minimum. This is noticeable as well for oncoming traffic as for the driver. In front of the car a less illuminated area is realized.

Automatic Lamp Control

Automatic Light is switched ON as default. It can be switched OFF by turning the light switch to OFF position. It will be switched ON again by doing so again. Automatic Light is only available if a rain sensor or rain/light sensor module in installed in the car. The rain/light sensor module will send the actual ambient light state (day/night) to the BCM. If Automatic Light is enabled, BCM will react on the message received from the rain/light sensor module by switching ON/OFF low beams.

Flash to Pass (Standard) RPO TT4

When the low beam headlamps are on and the turn signal/multifunction switch is momentarily placed in the flash to pass position, ground is applied to the turn signal/multifunction switch. The turn signal/multifunction switch applies ground to the BCM through the flash to pass switch signal circuit. The BCM then applies ground to the high beam relay control circuit. This energizes the high beam relay, closing the switch side contacts of the high beam relay, applying battery voltage to the left and right high beam fuses. Battery voltage is applied from the high beam fuses through the high beam voltage supply circuit to the high beam headlamp assemblies. This causes the high beam headlamps to illuminate at full brightness momentarily or until the flash to pass switch is released.

Flash to Pass (up level) RPO TT6

When the low beam headlamps are ON and the turn signal/multifunction switch is momentarily placed in the flash to pass position, ground is applied to the turn signal/multifunction switch. The turn signal/multifunction switch applies ground to the BCM through the flash to pass switch signal circuit. The BCM sends a message to the headlamp control module to lift the shutter from the Xenon lamp. This causes the Xenon lamp to illuminate the headlamp at full brightness momentarily or until the flash to pass switch is released.

Automatic Headlamp Leveling

The Automatic Headlamp Leveling Systems consist of the following components

  1. Ballast module - left
  2. Ballast module - right
  3. Headlamp leveling actuator - left
  4. Headlamp leveling actuator - right
  5. Headlamp control module
  6. Headlamp leveling sensor - front
  7. Headlamp leveling sensor - rear

The automatic headlamp leveling system automatically maintains the vertical alignment of the headlamps when the vehicle load and driving conditions change. The headlamp control module receives inputs from the front and rear headlamp leveling sensors to determine vehicle pitch. The headlamp leveling sensors send an output to the headlamp control module as the vehicle suspension compresses and rebounds. The headlamp control module calculates the difference in vehicle pitch and sends a command to the (HID) ballast. The ballast then drive the headlamp leveling actuators to the position commanded by the headlamp control module. The headlamp leveling system also monitors the performance of the HID bulb and ballast. When the headlamp switch is placed in the ON position the headlamps will go down, and then back up to the center position.

Daytime Running Lamps (DRL) without HID RPO TT4

The DRL bulbs are combined with the park lamps. One filament is for the DRL and one for the park lamps. The DRL will operate when the following conditions are met

  1. Engine is running.
  2. Headlamp switch in AUTOMATIC LIGHT position.
  3. The high and low beam headlamps are OFF.

By turning the headlamp switch in the OFF position the automatic light function and the DRL will be deactivated.

The ambient light sensor is used to monitor outside lighting conditions. The ambient light sensor provides a voltage signal that will vary between 0.2-4.9 V depending on outside lighting conditions. The HVAC control module provides a low reference ground and 5 V reference signals to the ambient light sensor. The BCM monitors the ambient light sensor signal circuit to determine if outside lighting conditions are correct for either DRL or low beam when the headlamp switch is in the AUTOMATIC LIGHT position. In daylight conditions, the BCM will command the DRL ON by applying ground to the left and right DRL relays via separate left and right DRL relay control circuits. When the BCM applies ground to the relay control circuits, the left and right DRL relay coils energize causing both relay switch contacts to close. With the left and right DRL relay switch contacts closed, battery voltage flows to the left and right DRL lamps. Any function or condition that turns on the headlamps will cancel DRL operation.

Daytime Running Lamps (DRL) with HID RPO TT6

The DRL are LEDs which are continuously illuminated when

  1. Ignition is switched ON.
  2. Engine is running.
  3. High and low beam headlamps are ON or OFF.
  4. Headlamp switch is in PARKING LIGHT, AUTOMATIC LIGHT or LOW BEAM position.

By turning the headlamp switch in the OFF position the automatic light function and the DRL will be deactivated.

The ambient light sensor is used to monitor outside lighting conditions. The ambient light sensor provides a voltage signal that will vary between 0.2-4.9 V depending on outside lighting conditions. The HVAC control module provides a low reference ground and 5 V reference to the ambient light sensor. The BCM monitors the ambient light sensor signal circuit to determine if outside lighting conditions are correct for only DRL or DRL and low beam when the headlamp switch is in the AUTOMATIC LIGHT position. In daylight conditions the BCM will command the DRL ON.

Front Fog Lamps

The front fog lamp relay is supplied with battery voltage at all times. The front fog lamp switch signal circuit is grounded momentarily by pressing the front fog lamp switch. The body control module (BCM) energizes the front fog lamp relay by applying ground to the front fog lamp relay control circuit. When the front fog lamp relay is energized, the relay switch contacts close and battery voltage is applied through the front fog lamp fuse to the front fog lamp supply voltage circuit which illuminates the front fog lamps.

Rear Fog Lamps

When the rear fog lamp switch is placed in the ON position, battery voltage is applied from the BCM to the rear fog lamps. Ground for the rear fog lamps is applied at all times.

The BCM will send a message via GMLAN serial data to the instrument panel cluster to enable the rear fog lamp indicator.

Park, Tail, License and Marker Lamps

The park lamps, tail lamps/LEDs and number plate lights are turned ON when the headlamp switch is placed in the Parking lights or Low beam position or anytime the headlights are requested. When the BCM receives a request from the headlamp switch to turn ON the park lamps the BCM a sends out a PWM signal, which illuminates the park lamps, tail lamps and number plate lights.

Turn Signal Lamps

Ground is applied at all times to the turn signal/multifunction switch. The turn signal lamps may only be activated with the ignition switch in the ON or START position. When the turn signal/multifunction switch is placed in either the TURN RIGHT or TURN LEFT position, ground is applied to the BCM through either the right turn or left turn signal switch signal circuit. The BCM then applies a pulsating voltage to the front and rear turn signal lamps through there respective voltage supply circuits. When a turn signal request is received by the BCM, a serial data message is sent to the instrument cluster requesting the respective turn signal indicator be pulsed ON and OFF.

Repeater Lamps

The repeater lamps are located in the front fender. The repeater lamps are used as additional turn signal lamps, and operate as described in the Turn Signal/Hazard Flasher Lamps description.

Hazard Flasher Lamps

The hazard flashers may be activated in any power mode. The hazard switch is permanently grounded. When the hazard switch is placed in the ON position, ground is applied through the hazard switch signal circuit to the BCM. The BCM supplies battery voltage to all turn signal lamps in an ON and OFF duty cycle. When the hazard switch is activated, the BCM sends a serial data message to the instrument cluster requesting both turn signal indicators to be cycled ON and OFF.

Stop Lamps

The brake pedal position (BPP) sensor is used to sense the action of the driver application of the brake pedal. The BPP sensor provides an analog voltage signal that will increase as the brake pedal is applied. The BCM provides a low reference signal and a 5 V reference voltage to the BPP sensor. When the variable signal reaches a voltage threshold indicating the brakes have been applied, the BCM will apply battery voltage to the stop lamp control circuit and center high mounted stop lamp control circuit. When the control circuit is energized the stop lamps are illuminated.

Backup Lamps

When the transmission is placed in the reverse position, the engine control module (ECM) sends a serial data message to the BCM. The message indicates that the gear selector is in the reverse position. The BCM applies battery voltage to the backup lamps. The backup lamps are permanently grounded. Once the driver moves the gear selector out of the reverse position, a message is sent by the ECM via serial data requesting the BCM to remove battery voltage from the backup lamp control circuit.

Battery Run Down Protection/Inadvertent Power

To provide battery run down protection, the exterior lamps will be deactivated automatically under certain conditions. The BCM monitors the state of the headlamp switch. If the park or headlamp switch is ON when the ignition switch is placed in either the CRANK or RUN position and then placed in the OFF position, the BCM initiates a 10 min timer. At the end of the 10 min, the BCM will turn OFF the control power output to the park and headlamp relay coils, deactivating the exterior lamps. This feature will be cancelled if any power mode other than OFF becomes active. The BCM will disable battery run down protection if any of the following conditions exist. The park or headlamp switch is placed in the ON to OFF position, and back to the ON position during battery run down protection. The BCM determined that the park or headlamp switch was not active when the ignition was turned OFF.

Interior Lamps

The interior lamps consist of 2 groups, those which can dim from the instrument panel cluster lamps dimmer switch and those that can not dim.

Courtesy/Illuminated Entry Lamps

The following lamps may be manually turned ON by placing the interior lamp switch in the ON position, or by opening a door while the switch is in the AUTO position.

  1. The dome lamp
  2. The liftgate lamps
  3. Courtesy lamps

The courtesy lamp supply voltage circuit of the body control module (BCM) supplies battery positive voltage to the dome lamp, the liftgate lamps and courtesy lamps. When any door is opened, the door jamb switch contacts close providing a door open input to the BCM. The BCM then provides a B+ to the interior lamps with the switch in the AUTO position. The interior lamps receive a ground when the switch is in the ON position.

Note. If the liftgate is opened after all the modules go to sleep, the dome light will not come on. The liftgate ajar switch input to the BCM will not wake up the BCM once it has gone to sleep, so the dome light will not come on. Once the BCM gets an input to wake it up, from remote keyless entry or a door handle, the dome light will turn on when the liftgate is opened.

If the driver inadvertently leaves any interior lamp ON, the BCM will turn it OFF after a 20 minute time-out.

The courtesy lamps will turn OFF immediately if the ignition switch is turned to the ON position or approximately 20 seconds after all doors are closed.

Keyless Entry Interior Illumination

When the BCM receives a door unlock command from the remote keyless entry transmitter, the BCM will flash the park lamps several times, illuminate the courtesy and park lamps, and illuminate the low beam headlamps at low intensity. The lamps will remain on until the ignition key is turned from the OFF position, a keyless entry transmitter door lock command is received, or after an approximate 20 second delay.

Interior Lamps Dimming

This group includes lamps which may dim. This group may use a combination of vacuum fluorescent illumination, LEDs and incandescent lamps.

  1. HVAC control module, head assembly
  2. Rear HVAC control module, head assembly
  3. Radio
  4. Rear seat audio
  5. The instrument panel cluster
  6. The PRNDL lamp, with the exception of the current gear select position
  7. Power window switches
  8. Various switches

When the ignition switch is turned to the ON position, the vacuum fluorescent display, radio, turns ON at maximum brightness. When the park lamps are ON, all incandescent back lighting turn ON at the dimming level indicated by the instrument panel cluster dimmer switch. At the same time all fluorescent display displays dim to match the indicated dimming level. When the headlamp switch is placed in the PARK position, the park lamp supply voltage circuit provides an input to the BCM. The BCM then supplies voltage to the instrument panel cluster dimmer switch through the dimming control circuit. The setting of the instrument panel cluster dimmer switch determines the amount of voltage that the instrument panel cluster dimmer switch supplies to the BCM. The BCM then sends a PWM voltage to all the interior lamps. All the fluorescent display and incandescent back lighting lamps are provided a specific voltage and are then grounded. When the headlight switch is turned to the park lamp or headlamp position, all incandescent back lighting turn ON at the dimming level indicated by the instrument panel cluster dimmer switch. When the instrument panel cluster dimmer switch is moved from minimum to maximum, all fluorescent display displays, as well as all incandescent back lighting respond from minimum intensity to maximum brightness in response to the instrument panel cluster dimmer switch.

Inadvertent Power

The BCM used in this vehicle controls the lighting system through circuits that enable the interior lamps. The BCM opens these enabling circuits shortly after the ignition switch is turned OFF with no lamp switch activity. If the ignition switch is turned to any position other than OFF, or if a lamp switch is activated during this period, the timer will reset itself.

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• Trailer Connector/Provision Schematics
• Component Connector End Views
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Control Module References
• Diagnostic Repair Verification
• Radio Control Assembly Replacement
• Steering Wheel Secondary/Configurable Control Schematics
• Body Control System Schematics
• Power Mode Description and Operation
• Relay Replacement (Attached to Wire Harness)
• Turn Signal Multifunction Switch Replacement
• Liftgate Center Applique Replacement
• Cruise Control Schematics
• Checking Aftermarket Accessories
• Door Ajar Indicator Malfunction
• Instrument Panel Insulator Panel Replacement - Left Side
• Fastener Caution
• Rear Compartment Floor Stowage Compartment Tray Replacement
• Front Bumper Fascia Replacement
• Front Compartment Side Sight Shield Replacement
• Halogen Bulb Warning
• Air Cleaner Assembly Replacement (LF1)
• Lifting and Jacking the Vehicle
• Tire and Wheel Removal and Installation
• Front Wheelhouse Liner Replacement
• DTC B0655
• Left Low Beam Inoperative
• Right Low Beam Inoperative
• Front Turn Signal Lamp Bulb Replacement (TT6,TT7,TT8 Passenger Side Headlamp)
• Brake Pedal Position Sensor Calibration
• Brake Pedal Position Sensor Replacement
• Headlamp Capsule Replacement (TT6, TT7, TT8)