Lighting Systems Buick LaCrosse I

Fastener Tightening Specifications

Fastener Tightening Specifications

Lighting Systems Schematic Icons Icon Icon Definition CAUTION: When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Refer to SIR DISABLING AND ENABLING ZONES . Failure to observe the correct procedure could cause deployment of the SIR components, personal injury or unnecessary SIR system repairs

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Ambient Light Sensor (C67) Connector Part Information OEM: 12047662 Service: 12085535 2-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A L-GN/BK 1137 DRL Ambient Light Sensor Signal B BK/WH 1551 Ground

Backup Lamp - Left Connector Part Information OEM: 12162084 (AFL) Service: See Catalog 2-Way Socket (GY) Pin Wire Color Circuit No. Function A D-GN 24 Backup Lamp Supply Voltage B BK 550 Ground

Backup Lamp - Right Connector Part Information OEM: 16530675 12162084 (AFL) Service: See Catalog 2-Way Socket (GY) Pin Wire Color Circuit No. Function A D-GN 24 Backup Lamp Supply Voltage B BK 750 Ground

Brake Pedal Position Sensor Connector Part Information OEM: 15332132 Service: 88953364 3-Way F GT 150 Series (BK) Pin Wire Color Circuit No. Function A GY 598 10-Volt Reference B L-GN 526 Stop Lamp Switch Signal C BK 552 Low Reference

Center High Mounted Stop Lamp (CHMSL) Connector Part Information OEM: 12052641 Service: See Catalog 2-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A WH 1 Stop Lamp Switch Signal B BK 2 Ground

Dome/Reading Lamp - Left Connector Part Information OEM: 12047781 Service: 12101864 3-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A OG 1732 Inadvertent Power Courtesy Lamp (DH6) B BK 750 Ground C GY/BK 690 Courtesy Lamp Supply Voltage

Dome/Reading Lamp - Right Connector Part Information OEM: 12047781 Service: 12101864 3-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A OG 1732 Inadvertent Power Courtesy Lamp (DH6) B BK 750 Ground C GY/BK 690 Courtesy Lamp Supply Voltage

Fog Lamp - Left (T96) Connector Part Information OEM: 12124819 Service: 12085498 2-Way F Metri-Pack 280 Series Sealed (BK) Pin Wire Color Circuit No. Function A PU 34 Fog Lamps Supply Voltage B BK 1250 Ground

Fog Lamp - Right (T96) Connector Part Information OEM: 12124819 Service: 12085498 2-Way F Metri-Pack 280 Series Sealed (BK) Pin Wire Color Circuit No. Function A PU 34 Fog Lamps Supply Voltage B BK 1250 Ground

Headlamp - High Beam - Left Connector Part Information OEM: 12124817 Service: See Catalog 2-Way F Metri-Pack 280 Series Sealed (GY) Pin Wire Color Circuit No. Function A D-GN/BK 711 Left Headlamp High Beam Supply Voltage B BK 1350 Ground BK 1350 Ground

Headlamp - High Beam - Right Connector Part Information OEM: 12124817 Service: See Catalog 2-Way F Metri-Pack 280 Series Sealed (GY) Pin Wire Color Circuit No. Function A D-GN/BK 311 Right Headlamp High Beam Supply Voltage B BK 150 Ground BK 150 Ground

Headlamp - Low Beam - Left Connector Part Information OEM: 15393198 Service: See Catalog 2-Way F Metri-Pack 280 Series Sealed (BK) Pin Wire Color Circuit No. Function A TN/WH 712 Left Headlamp Low Beam Supply Voltage B BK 1350 Ground

Headlamp - Low Beam - Right Connector Part Information OEM: 15393198 Service: See Catalog 2-Way F Metri-Pack 280 Series Sealed (BK) Pin Wire Color Circuit No. Function A TN/WH 312 Right Headlamp Low Beam Supply Voltage B BK 150 Ground

I/P Compartment Lamp Switch Connector Part Information OEM: 12047662 Service: 12085535 2-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A OG 1732 Inadvertent Power Courtesy Lamp B BK 1450 Ground

I/P Courtesy Lamp - Left Connector Part Information OEM: 12084388 Service: See Catalog 2-Way Lamp Socket Wedge Base W-2 (BK) Pin Wire Color Circuit No. Function A GY/BK 690 Courtesy Lamp Supply Voltage B BK 1450 Ground

I/P Courtesy Lamp - Right Connector Part Information OEM: 12084388 Service: See Catalog 2-Way Lamp Socket Wedge Base W-2 (BK) Pin Wire Color Circuit No. Function A GY/BK 690 Courtesy Lamp Supply Voltage B BK 1450 Ground

Lamp Assembly Switch Connector Part Information OEM: 15324433 (Delphi) IL-AG5-185-D3C1 (JAE) Service: 15324433 18-Way F Socket Housing (GN) Pin Wire Color Circuit No. Function 1 BN/WH 230 I/P Dimming Return 2 PK/BK 1597 Courtesy Lamps Switch On Signal 3 - - Not Used 4 GY/BK 1598 I/P Dimming Return 5 WH 103 Headlamp Switch Headlamps On Signal 6 BN/WH 301 Park Lamp Switch On Signal 7 OG 192 Front Fog Lamp Switch Signal (T96) 8 - - Not Used 9 PK 1444 I/P Dimming Control 10 RD/WH 812 I/P Dimming Voltage Reference 11-12 - - Not Used 13 BK 1450 Ground 14 GY 8 Instrument Panel Lamp Supply Voltage 15-16 - - Not Used 17 BK/WH 1551 Ground 18 L-BU 1872 Exterior Lamps Off Input

License Lamp - Left Connector Part Information OEM: 12162084 Service: See Catalog 2-Way Lamp Socket Wedge Base W-2 (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage B BK 550 Ground

License Lamp - Right Connector Part Information OEM: 12162084 Service: See Catalog 2-Way Lamp Socket Wedge Base W-2 (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage B BK 550 Ground

Marker Lamp - LF Connector Part Information OEM: 15317651 Service: See Catalog 2-Way Lamp Socket Wedge Base W2 (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage B BK 1350 Ground

Marker Lamp - LR Connector Part Information OEM: 15317651 Service: See Catalog 2-Way Lamp Socket Wedge Base W2 (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage B BK 550 Ground

Marker Lamp - RF Connector Part Information OEM: 15317651 Service: See Catalog 2-Way Lamp Socket Wedge Base W2 (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage B BK 1250 Ground

Marker Lamp - RR Connector Part Information OEM: 15317651 Service: See Catalog 2-Way Lamp Socket Wedge Base W2 (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage B BK 750 Ground

Park/Turn Signal Lamp - LF Connector Part Information OEM: 12040977 Service: 12085492 3-Way F Metri-Pack 280 Series Sealed (BK) Pin Wire Color Circuit No. Function A L-BU/WH 1314 Left Front Turn Signal Lamp Supply Voltage B BN 9 Park Lamp Supply Voltage C BK 1250 Ground

Park/Turn Signal Lamp - RF Connector Part Information OEM: 12040977 Service: 12085492 3-Way F Metri-Pack 280 Series Sealed (BK) Pin Wire Color Circuit No. Function A L-BU/WH 1314 Right Front Turn Signal Lamp Supply Voltage B BN 9 Park Lamp Supply Voltage C BK 1250 Ground

PRNDL Lamp Connector Part Information OEM: 12162711 Service: See Catalog 2-Way Lamp Socket Wedge Base W2 (BK) Pin Wire Color Circuit No. Function A BU 8 Instrument Panel Lamp Supply Voltage B BU 550 Ground

Rear Compartment Courtesy Lamp Connector Part Information OEM: 12047662 Service: 12085535 2-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A OG 1732 Inadvertent Power Courtesy Lamp B OG/BK 737 Rear Compartment Courtesy Lamp Switch

Sunload Sensor Assembly (CJ2) Connector Part Information OEM: 12064760 Service: 12085208 4-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A L-BU/BK 590 Driver Sunload Sensor Signal B GY 1548 Passenger Sunload Sensor Signal C BK/WH 1551 Ground D L-GN/BK 1137 DRL Ambient Light Sensor Signal

Tail Lamp - Left - Lower Connector Part Information OEM: 16530675 (AFL) Service: See Catalog 2-Way Socket (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage BN 9 Park Lamp Supply Voltage B BK 150 Ground BK 150 Ground

Tail Lamp - Left - Upper Connector Part Information OEM: 16530675 (AFL) Service: See Catalog 2-Way Socket (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage BN 9 Park Lamp Supply Voltage B BK 150 Ground BK 150 Ground

Tail Lamp - Right - Lower Connector Part Information OEM: 16530675 (AFL) Service: See Catalog 2-Way Socket (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage BN 9 Park Lamp Supply Voltage B BK 150 Ground BK 150 Ground

Tail Lamp - Right - Upper Connector Part Information OEM: 16530675 (AFL) Service: See Catalog 2-Way Socket (GY) Pin Wire Color Circuit No. Function A BN 9 Park Lamp Supply Voltage BN 9 Park Lamp Supply Voltage B BK 150 Ground BK 150 Ground

Tail/Stop and Turn Signal Lamp - Left Connector Part Information OEM: 12160394 (AFL) Service: See Catalog 3-Way Socket (NA) Pin Wire Color Circuit No. Function A YE 18 Right Rear Stop/Turn Lamp Supply Voltage B BN 9 Park Lamp Supply Voltage G BK 550 Ground

Tail/Stop and Turn Signal Lamp - Right Connector Part Information OEM: 12160394 (AFL) Service: See Catalog 3-Way Socket (NA) Pin Wire Color Circuit No. Function A YE 18 Right Rear Stop/Turn Lamp Supply Voltage B BN 9 Park Lamp Supply Voltage G BK 750 Ground

Turn Signal/Multifunction Switch C1 Connector Part Information OEM: 12059800 Service: 15306169 5-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A BN 1356 Flash To Pass Switch Signal B-C - - Not Used D BK/WH 1551 Ground E PU 524 Headlamp Dimmer Switch High Beam Signal

Turn Signal/Multifunction Switch C2 Connector Part Information OEM: 12064862 Service: 12126438 8-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A-E - - Not Used F L-BU/WH 1414 Left Turn Signal Switch Signal G BK/WH 1551 Ground H D-BU/WH 1415 Right Turn Signal Switch Signal

Turn Signal/Multifunction Switch C3 Connector Part Information OEM: 15339058 Service: See Catalog 7-Way F Metri-Pack 150 Series (GY) Pin Wire Color Circuit No. Function G - - Not Used H BK/WH 1251 Ground J PK 94 Windshield Washer Switch Signal K L-GN 1715 Windshield Wiper Switch High Signal L L-BU 1714 Windshield Wiper Switch Low Signal M-N - - Not Used

Vanity Mirror Lamp - Left (DH6) Connector Part Information OEM: 12047662 Service: 12085535 2-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A OG 1732 Inadvertent Power Courtesy Lamp B BK 750 Ground

Vanity Mirror Lamp - Right (DH6) Connector Part Information OEM: 12047662 Service: 12085535 2-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A OG 1732 Inadvertent Power Courtesy Lamp B BK 750 Ground

DIAGNOSTIC CODE INDEX

DIAGNOSTIC CODE INDEX

Begin the system diagnosis with the Diagnostic System Check - Vehicle in Vehicle DTC Information. The Diagnostic System Check will provide the following information

1. The identification of the control modules which command the system
2. The ability of the control modules to communicate through the serial data circuit
3. The identification of any stored diagnostic trouble codes (DTCs) and their status

The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and where the procedure is located.

Scan Tool Output Controls

Body Control Module (BCM)

Scan Tool Data List

Scan Tool Data List

BCM Scan Tool Data Definitions

The BCM Scan Tool Data Definitions contains a brief description of all Lighting System related BCM parameters available on the scan tool.

Circuit Description

The fog lamp relay is energized by the fog lamp switch only when the body control module (BCM) has activated the fog lamp enable circuit that supplies the fog lamp switch. The BCM will only activate the fog lamp enable circuit if the following conditions exist

1. The ignition switch must be in the RUN position.
2. The headlamp switch must be in the park or headlamp ON position.
3. The headlamp dimmer switch must be in the low beam position.

DTC Descriptor

This diagnostic procedure supports the following DTC

DTC B2525 Front Fog Lamp Enable Circuit

Conditions for Running the DTC

The BCM must be commanding the fog lamp relay to energize.

Conditions for Setting the DTC

1. The fault code will set when the fog lamp enable circuit is active and a short to battery positive voltage, an open or a short to ground is present.
2. The condition above must be present for more than 0.3 seconds.
3. If the short to battery positive voltage is on the output side of the fog lamp switch, the fault will only set when the fog lamp switch is in the ON position.

Action Taken When the DTC Sets

The BCM stores DTC B2525 in memory.

Conditions for Clearing the DTC

1. A current DTC B2525 will clear if the short to battery positive voltage, a short to ground or an open in the fog lamp enable circuit is no longer detected by the BCM.
2. A history DTC B2525 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
3. The BCM receives a clear code command from the scan tool.

Diagnostic Aids

1. If the DTC B2525 is a history DTC, the fault may be intermittent. Refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.
2. The following conditions may cause an intermittent malfunction to occur: An intermittent short to battery positive voltage, a short to ground or an open in the fog lamp enable circuit. The fog lamp relay coil is intermittently shorted to battery. The BCM is intermittently shorted to battery positive voltage, shorted to ground or an open.

DTC B2525

When the body control module (BCM) receives a class 2 signal from the power control module (PCM) indicating the gear selector is in the REVERSE position, the BCM applies battery positive voltage to the backup lamps voltage supply circuit. The backup lamps are grounded at G301 for the left backup lamp and G302 for the right backup lamp.

This diagnostic procedure supports the following DTC

DTC B2545 Backup Lamps Circuit

The battery voltage must be between 9-16 volts.

DTC B2545 is set either when the backup lamps supply voltage circuit is shorted to ground or opened or if the CHMSL/Bkup fused voltage supply circuit to the BCM is shorted to ground or opened.

The backup lamps will not operate.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History DTCs can be cleared using a scan tool.

Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

DTC B2545

When the body control module (BCM) receives a ground signal from the headlamp dimmer switch high beam signal or flash to pass (FTP) switch signal commanding to illuminate the high beam headlamps, the BCM will energize the high beam relay by grounding the HI BEAM relay control circuit.

This diagnostic procedure supports the following DTC

DTC B2580 Headlamp High Beam Control Circuit

The battery voltage must be between 9-16 volts.

1. When the BCM receives a high beam headlamp OFF command and the high beam headlamp relay control circuit is shorted to ground.
2. When the BCM receives a high beam headlamp ON command and the high beam headlamp relay control circuit is shorted to voltage or open.

The high beam headlamps will not operate or will remain always on.

Conditions for Clearing the MIL/DTC

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

DTC B2580

The body control module (BCM) applies a voltage reference through the instrument panel (I/P) dimming voltage reference circuit to the interior lamp switch. When the switch is placed to the desired position, the dimmed voltage setting is applied from the interior lamp switch through the I/P dimming return circuit to the BCM. The BCM applies the dimmed voltage to the I/P lamps supply voltage circuit.

This diagnostic procedure supports the following DTC

DTC B2610 I/P Dimming Circuit

The battery voltage must be between 9-16 volts.

1. When the BCM receives a instrument panel controls illumination lamp request signal and the instrument panel dimming reference circuit is shorted to ground or short to battery positive voltage.
2. When the BCM is not receiving a instrument panel controls illumination lamp request signal and the instrument panel lamps dimming signal circuit is shorted to battery positive voltage or open.

The instrument panel illumination lamps and the controls illumination lamps will not operate or are always ON.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections .

DTC B2610

The body control module (BCM) monitors the ambient light sensor signal circuit in order to determine if the daytime running lights (DRL) or the auto headlights (ALC) should be turned ON in the AUTO mode. When the BCM senses the ambient light sensor voltage is between 1.75-4.9 volts, either the DRL will be commanded ON or the ALC will be commanded ON.

This diagnostic procedure supports the following DTC

DTC B2645 Ambient Light Circuit

The system voltage must be between 9-16 volts.

1. When the ambient light sensor signal voltage is less than 1.75 volts.
2. When the ambient light sensor signal voltage is more than 4.9 volts.
3. If there is a short to battery positive voltage or a short to ground on the 10-volt reference circuit of the brake pedal position sensor (BPPS).

The ALC will remain ON in any ambient light state.

1. This DTC will clear immediately after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. Use a scan tool in order to clear history and current DTCs.

DTC B2645

The body control module (BCM) supplies battery positive voltage to the center high-mounted stop lamp (CHMSL), powertrain control module (PCM), engine control module (ECM) and antilock brake system (ABS) module through the stop lamp supply voltage circuits when the brakes are applied.

This diagnostic procedure supports the following DTC

DTC B3445 Stop Lamp Circuit

The battery voltage must be between 9-16 volts.

DTC B3445 will set when the BCM detect an open or short to ground in the stop lamp supply voltage circuits.

The CHMSL will not operate.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

DTC B3445

The body control module (BCM) controls the park lamp relay through the park lamp relay control circuit. The BCM grounds the park lamp relay control circuit which energizes the PK LP relay.

This diagnostic procedure supports the following DTC

DTC B3838 Park Lamp Relay Control Circuit

The BCM must be commanding the park lamp relay to energize.

1. The BCM detects a short to battery positive voltage, short to ground, poor connection or an open in the park lamp relay control circuit when it is trying to energize the PK LP relay.
2. The BCM detects a short to ground in the switched park lamp voltage supply circuit.
3. The condition above must be present for more than 0.3 seconds.

The BCM stores DTC B3838 in memory.

1. A fault in the park lamp relay control circuit is no longer detected by the BCM when the PK LP relay is commanded to energize. After the fault is removed the ignition must be cycled to clear the code.
2. A short to ground in the switched park lamp voltage supply circuit is no longer detected by the BCM when the PK LP relay is commanded to energize. After the fault is removed the ignition must be cycled to clear the code.
3. A history DTC B3838 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
4. The BCM receives a clear code command from the scan tool.

1. If the DTC B3838 is a history DTC, the fault may be intermittent. Refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.
2. The following conditions may cause an intermittent malfunction to occur: An intermittent fault in the park lamp relay coil control circuit. The park lamp relay coil is shorted to battery positive voltage. The BCM is shorted to battery positive voltage. An intermittent short to ground in the switched park lamp voltage supply circuit.

DTC B3838

Ground is applied by the turn signal switch. When the turn signal switch is placed in the turn left position, ground is applied to the body control module (BCM) through the left turn signal switch circuit. The BCM then applies a pulsating voltage to the LF and LR turn signal lamps through the LF and LR turn signal lamp supply voltage circuits.

This diagnostic procedure supports the following DTC

DTC B3948 Left Front Turn Signal Circuit

The battery voltage must be between 9-16 volts.

A short to ground or an open in the LF turn signal lamp supply voltage circuit is present for longer then 0.1 seconds.

The left front turn signal lamp does not work.

1. The DTC will clear on current status after the condition for setting the fault is corrected.
2. Will set a history code which will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Check the LF turn lamp bulb. If the bulb is open, DTC B3948 will be set.
2. If the DTC is a history DTC, the fault may be interment. Refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.
3. An interment short to ground or an open in the following locations may cause an intermittent malfunction to occur: The BCM The underhood electrical center The left front turn signal lamp supply voltage circuit

DTC B3948

Ground is applied by the turn signal switch. When the turn signal switch is placed in the turn right position, ground is applied to the body control module (BCM) through the right turn signal switch circuit. The BCM applies a pulsating voltage to the RF and RR turn signal lamps through the RF and RR turn signal lamp supply voltage circuits.

This diagnostic procedure supports the following DTC

DTC B3949 Right Front Turn Signal Circuit

The battery voltage must be between 9-16 volts.

A short to ground or an open in the RF turn signal lamp supply voltage circuit is present for longer then 0.1 seconds.

The right front turn signal lamp does not work.

1. The DTC will clear on current status after the condition for setting the fault is corrected.
2. Will set a history code which will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Check the RF turn lamp bulb. If the bulb is open, DTC B3948 will be set.
2. If the DTC is a history DTC, the fault may be interment. Refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.
3. An interment short to ground or an open in the following locations may cause an intermittent malfunction to occur: The BCM The underhood electrical center The right front turn signal lamp supply voltage circuit

DTC B3949

Ground is applied by the turn signal switch. When the turn signal switch is placed in the turn left position, ground is applied to the body control module (BCM) through the left turn signal switch circuit. The BCM then applies a pulsating voltage to the LF and LR turn signal lamps through the LF and LR turn signal lamp supply voltage circuits.

This diagnostic procedure supports the following DTC

DTC B3950 Left Rear Turn Signal Circuit

The battery voltage must be between 9-16 volts.

A short to ground or an open in the LR turn signal lamp supply voltage circuit is present for longer then 0.1 seconds.

The left rear turn signal lamp does not work.

1. The DTC will clear on current status after the condition for setting the fault is corrected.
2. Will set a history code which will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Check the LR turn lamp bulb. If the bulb is open, DTC B3950 will be set.
2. If the DTC is a history DTC, the fault may be interment. Refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.
3. An interment short to ground or an open in the following locations may cause an intermittent malfunction to occur: The BCM The left rear turn signal lamp supply voltage circuit

DTC B3950

Ground is applied by the turn signal switch. When the turn signal switch is placed in the turn right position, ground is applied to the body control module (BCM) through the right turn signal switch circuit. The BCM applies a pulsating voltage to the RF and RR turn signal lamps through the RF and RR turn signal lamp supply voltage circuits.

This diagnostic procedure supports the following DTC

DTC B3951 Right Rear Turn Signal Circuit

The battery voltage must be between 9-16 volts.

A short to ground or an open in the RR turn signal lamp supply voltage circuit is present for longer then 0.1 seconds.

The right rear turn signal lamp does not work.

1. The DTC will clear on current status after the condition for setting the fault is corrected.
2. DTC B3951 will set a history code which will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Check the RR turn lamp bulb. If the bulb is open, DTC B3950 will be set.
2. If the DTC is a history DTC, the fault may be interment. Refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.
3. An interment short to ground or an open in the following locations may cause an intermittent malfunction to occur: The BCM The right rear turn signal lamp supply voltage circuit

DTC B3951

The body control module (BCM) applies a ground through the brake pedal position sensor reference low circuit to the brake pedal position sensor. The BCM supplies a 10-volt reference through the brake sensor reference voltage circuit to the brake pedal position sensor (BPPS). When the brake pedal is being applied, the BPPS then sends a variable voltage signal through the brake sensor signal circuit to the BCM.

This diagnostic procedure supports the following DTC

DTC C0277 Brake Pedal Position Sensor Circuit

The battery voltage must be between 9-16 volts.

1. An open or a short to battery positive voltage or ground on the low reference circuit of the BPPS is present.
2. A short to ground or an open in the stop lamp switch signal circuit is present.
3. A short to ground or an open in the 10-volt reference circuit on the BPPS.
4. A short to ground in the instrument panel (I/P) dimming voltage reference circuit.
5. A malfunctioning BPPS or BCM.

The stop lamps will not function correctly.

1. The DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. A History or current DTC can be cleared using a scan tool.

Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections .

DTC C0277

The body control module (BCM) applies a ground through the brake sensor reference low circuit to the brake pedal position sensor. The BCM supplies a 10-volt reference through the brake pedal sensor reference voltage circuit to the brake pedal position sensor. When the brake pedal is being applied, the brake pedal position sensor then sends a variable voltage signal through the brake sensor signal circuit to the BCM.

This diagnostic procedure supports the following DTC

DTC C0278 Brake Pedal Position Sensor Not Calibrated

The battery voltage must be between 9-16 volts.

DTC C0278 will set if the brake position sensor is out of calibration.

The stop lamps will not function correctly.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles with out a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. If DTC C0278 sets then recalibrate the brake position sensor.
2. Perform a visual inspection for a loose or poor connection at all related components. Refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.

DTC C0278

The body control module (BCM) applies a ground through the brake pedal position sensor reference low circuit to the brake pedal position sensor (BPPS). The BCM supplies a 10-volt reference through the brake pedal sensor reference voltage circuit to the BPPS. When the brake pedal is being applied, the brake pedal sensor then sends a variable voltage signal through the BPPS signal circuit to the BCM.

This diagnostic procedure supports the following DTC

DTC C0283 Brake Pedal Position Sensor Circuit Low

The battery voltage must be between 9.0-16.0 volts.

1. An open or a short to battery positive voltage or ground on the low reference circuit is present.
2. A short to ground or an open in the stop lamp switch signal circuit is present.
3. A open or a short to ground in the 10-volt reference circuit of the brake pedal position sensor.
4. A short to ground or a short to battery positive in the I/P dimmer control circuit.
5. A malfunctioning brake pedal position sensor or BCM.

The stop lamps will turn on steady.

1. The DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. A History or current DTC can be cleared using a scan tool.

Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections .

DTC C0283

The body control module (BCM) applies a ground through the brake pedal sensor reference low circuit to the BPPS. The BCM supplies a 10-volt reference through the brake pedal sensor reference voltage circuit to the BPPS. When the brake pedal is being applied, the BPPS then sends a variable voltage signal through the brake pedal sensor signal circuit to the BCM.

This diagnostic procedure supports the following DTC

DTC C0870 Brake Pedal Position Sensor Reference Output Circuit

The battery voltage must be between 9-16 volts.

1. A short to ground or an open in the brake pedal position sensor voltage reference circuit is present.
2. A short battery positive voltage in the brake pedal position sensor voltage reference circuit is present.

The stop lamps will not function correctly.

1. The DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. A History or current DTC can be cleared using a scan tool.

Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections .

DTC C0870

The body control module (BCM) receives a signal from the brake pedal position sensor through the stop lamp switch signal circuit. The BCM then applies voltage through the stop lamp voltage supply circuit to the powertrain control module (PCM), electronic brake control module (EBCM) and the stop lamps.

This diagnostic procedure supports the following DTC

DTC P0572 Cruise Control Brake Pedal Position Sensor Circuit High Voltage

1. The vehicle has cycled from 0-60 km/h (0-37 mph) 3 times in one ignition cycle.
2. Continuous once the previous criteria have been met.

The PCM detects voltage on the stop lamp voltage supply circuit when the circuit should be open.

1. The PCM stores the DTC information into memory when the diagnostic runs and fails.
2. The malfunction indicator lamp (MIL) will not illuminate.
3. The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.

1. A last test failed or current DTC, clears when the diagnostic runs and does not fail.
2. A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Use a scan tool in order to clear the DTC.

1. Verify that the brake pedal position sensor is adjusted properly. Refer to «Brake Pedal Position Sensor Calibration»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__brake-pedal-position-sensor-calibration) .
2. Test drive the vehicle if a switch or circuit condition cannot be located. An intermittent condition may be duplicated during a test drive.
3. For an intermittent, refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.

Test Description

The number below refers to the step number on the diagnostic table.

1. 2: This step determines if the fault is present.

DTC P0572

The body control module (BCM) receives a signal from the brake pedal position sensor through the stop lamp switch signal circuit. The BCM then applies voltage through the stop lamp voltage supply circuit to the powertrain control module (PCM), electronic brake control module (EBCM) and the stop lamps.

This diagnostic procedure supports the following DTC

DTC P0573 Cruise Brake Pedal Position Sensor Circuit Low Voltage

1. Vehicle has cycled from 0-60 km/h (0-37 mph) 3 times in one ignition cycle.
2. Continuous once the previous criteria have been met.

The PCM detects an open or short to ground on the stop lamp voltage supply circuit when the voltage should be present.

1. The PCM stores the DTC information into memory when the diagnostic runs and fails.
2. The malfunction indicator lamp (MIL) will not illuminate.
3. The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.

1. A last test failed or current DTC, clears when the diagnostic runs and does not fail.
2. A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Use a scan tool in order to clear the DTC.

1. Verify that the brake pedal position sensor switch is adjusted properly. Refer to «Brake Pedal Position Sensor Calibration»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__brake-pedal-position-sensor-calibration) .
2. Test drive the vehicle if a switch or circuit condition cannot be located. An intermittent condition may be duplicated during a test drive.
3. For an intermittent, refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) in Wiring Systems.

The number below refers to the step number on the diagnostic table.

1. 2: This step determines if the fault is present.

DTC P0573

The body control module (BCM) receives a signal from the brake pedal position sensor through the stop lamp switch signal circuit. The BCM then applies voltage through the stop lamp voltage supply circuit to the powertrain control module (PCM), engine control module (ECM) and the stop lamps.

This diagnostic procedure supports the following DTC

DTC P0504 Brake Switch 1-2 Correlation

1. The vehicle has cycled from 0-60 km/h (0-37 mph) 3 times in 1 ignition cycle.
2. Continuous once the previous criteria have been met.

1. Both discrete input and serial data message brake applied/unapplied data do not match for at least 2 seconds, for 10 occurrences.
2. Invalid voltage signal on the stop lamp signal for at least 2 seconds.

1. The ECM stores the DTC information into memory when the diagnostic runs and fails.
2. The malfunction indicator lamp (MIL) will not illuminate.
3. The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records.

1. A last test failed or current DTC, clears when the diagnostic runs and does not fail.
2. A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Use a scan tool in order to clear the DTC.

1. Verify that the brake pedal position sensor is adjusted properly. Refer to «Brake Pedal Position Sensor Calibration»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__brake-pedal-position-sensor-calibration) .
2. Test drive the vehicle if a switch or circuit condition cannot be located. An intermittent condition may be duplicated during a test drive.
3. For an intermittent, refer to «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing) .

The number below refers to the step number on the diagnostic table.

1. 2: This step determines if the fault is present.

DTC P0504

1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information. No DTCs are set. The control modules can communicate via the serial data link.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to «Exterior Lighting Systems Description and Operation»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems) or «Interior Lighting Systems Description and Operation»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems) .

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the lighting system. Refer to «Checking Aftermarket Accessories»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__checking-aftermarket-accessories) in Wiring Systems.
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

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

1. «Backup Lamps Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__backup-lamps-always-on)
2. «Backup Lamps Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__backup-lamps-inoperative)
3. «Courtesy Lamps Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__courtesy-lamps-always-on)
4. «Courtesy Lamps Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__courtesy-lamps-inoperative)
5. «Daytime Running Lamps (DRL) Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__daytime-running-lamps-drl-inoperative)
6. «Fog Lamps Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__fog-lamps-always-on)
7. «Fog Lamps Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__fog-lamps-inoperative)
8. «Hazard Lamps Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__hazard-lamps-always-on)
9. «Hazard Lamps Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__hazard-lamps-inoperative)
10. «Headlamps Always On - Low or High Beam»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__headlamps-always-on-low-or)
11. «Headlamps Inoperative - High Beams»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__headlamps-inoperative-high-beams)
12. «Headlamps Inoperative - Low Beams»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__headlamps-inoperative-low-beams)
13. «Headlamps Inoperative - Flash to Pass»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__headlamps-inoperative-flash-to-pass)
14. «Illuminated Entry Lamps Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__illuminated-entry-lamps-inoperative)
15. «Interior Backlighting Does Not Dim»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__interior-backlighting-does-not-dim)
16. «Interior Backlighting Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__interior-backlighting-inoperative)
17. «Instrument Panel (I/P) Compartment Lamp Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__instrument-panel-ip-compartment-lamp-inoperative)
18. «Instrument Panel (I/P) Compartment Lamp Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__instrument-panel-ip-compartment-lamp-always)
19. «Park, License and Tail Lamps Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__park-license-and-tail-lamps-always)
20. «Park, License and Tail Lamps Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__park-license-and-tail-lamps-inoperative)
21. «Reading Lamp(s) Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__reading-lamps-always-on)
22. «Reading Lamp(s) Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__reading-lamps-inoperative)
23. «Rear Compartment Lamp(s) Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__rear-compartment-lamps-always-on)
24. «Rear Compartment Lamp(s) Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__rear-compartment-lamps-inoperative)
25. «Stop Lamps Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__stop-lamps-always-on)
26. «Stop Lamps Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__stop-lamps-inoperative)
27. «Turn Signal Lamps and/or Indicators Always On or Flashing»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__turn-signal-lamps-andor-indicators-always)
28. «Turn Signal Lamps and/or Indicators Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__turn-signal-lamps-andor-indicators-inoperative)
29. «Vanity Mirror Lamp(s) Always On»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__vanity-mirror-lamps-always-on)
30. «Vanity Mirror Lamp(s) Inoperative»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__vanity-mirror-lamps-inoperative)

Backup Lamps Always On

Backup Lamps Always On

Backup Lamps Inoperative

Backup Lamps Inoperative

Courtesy Lamps Always On

Courtesy Lamps Always On

Courtesy Lamps Inoperative

Courtesy Lamps Inoperative

Daytime Running Lamps (DRL) Inoperative

Daytime Running Lamps (DRL) Inoperative

Fog Lamp Indicator Always On

Fog Lamp Indicator Always On

Fog Lamp Indicator Inoperative

Fog Lamp Indicator Inoperative

Fog Lamps Always On

Fog Lamps Always On

Fog Lamps Inoperative

Fog Lamps Inoperative

Hazard Lamps Always On

Hazard Lamps Always On

Hazard Lamps Inoperative

Hazard Lamps Inoperative

Headlamps Always On - Low or High Beam

Headlamps Always On - Low or High Beam

Headlamps Inoperative - High Beams

Headlamps Inoperative - High Beams

Headlamps Inoperative - Low Beams

Headlamps Inoperative - Low Beams

Headlamps Inoperative - Flash to Pass

Headlamps Inoperative - Flash to Pass

High Beam Indicator Always On

High Beam Indicator Always On

High Beam Indicator Inoperative (Standard)

High Beam Indicator Inoperative (Standard)

Illuminated Entry Lamps Inoperative

Illuminated Entry Lamps Inoperative

Interior Backlighting Does Not Dim

Interior Backlighting Does Not Dim

Interior Backlighting Inoperative

Interior Backlighting Inoperative

Instrument Panel (I/P) Compartment Lamp Inoperative

Instrument Panel (I/P) Compartment Lamp Inoperative

Instrument Panel (I/P) Compartment Lamp Always On

Instrument Panel (I/P) Compartment Lamp Always On

Park, License and Tail Lamps Always On

Park, License and Tail Lamps Always On

Park, License and Tail Lamps Inoperative

Park, License and Tail Lamps Inoperative

Reading Lamp(s) Always On

Reading Lamp(s) Always On

Reading Lamp(s) Inoperative

Reading Lamp(s) Inoperative

Rear Compartment Lamp(s) Always On

Rear Compartment Lamp(s) Always On

Rear Compartment Lamp(s) Inoperative

Rear Compartment Lamp(s) Inoperative

Stop Lamps Always On

Stop Lamps Always On

Stop Lamps Inoperative

Stop Lamps Inoperative

Turn Signal Lamps and/or Indicators Always On or Flashing

Turn Signal Lamps and/or Indicators Always On or Flashing

Turn Signal Lamps and/or Indicators Inoperative

Turn Signal Lamps and/or Indicators Inoperative

Vanity Mirror Lamp(s) Always On

Vanity Mirror Lamp(s) Always On

Vanity Mirror Lamp(s) Inoperative

Vanity Mirror Lamp(s) Inoperative

Scheme 20

Headlamp, Fog Lamp, Turn Signal Lamp, Side Marker Lamp Replacement - Front

Scheme 21

Tail Lamp, Turn Signal Lamp, High Mount Stop Lamp, License Lamp, Backup Lamp Replacement - Rear

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

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 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 the class 2 communication bus.

Calibration Procedure

1. Turn ON the ignition, with the engine OFF.
2. Install a scan tool, select the proper vehicle and options.
3. Select the BPP sensor calibration procedure from the BCM 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.

Removal Procedure

1. Remove the instrument panel (I/P) insulator. Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
2. Disengage but do not remove the connector position assurance (CPA) on the connector. Disconnect the electrical connector (2).
3. Remove the screw.
4. Remove the brake pedal position sensor.

Installation Procedure

1. Apply adhesive GM P/N 12345493 (Canadian P/N 10953488) to the screw.
2. Position the sensor fork to the pin.
3. Rotate the sensor in order to align the sensor locator to the hole in the extension bracket.
4. Install the brake pedal position sensor screw. Tighten: Tighten the screw to 2.0 N.m (18 lb in).
5. Connect the electrical connector (2). Engage the CPA. The CPA will not engage if the connector is not attached properly.
6. Calibrate the sensor. Refer to «Brake Pedal Position Sensor Calibration»(/buick/lacrosse/i-2004-2009/remont/exterior-lights/#lighting-systems__brake-pedal-position-sensor-calibration) .
7. Install the I/P insulator. Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.

Scheme 22

Headlamp Switch Replacement

Scheme 23

Daytime Running Lamps (DRL) Ambient Light Sensor Replacement

1. Remove the front door trim panel enough to access the courtesy lamp. Refer to «Trim Panel Replacement - Side Front Door»(/buick/lacrosse/i-2004-2009/remont/door-locks-anti-theft-systems/#door-system-mirror-system-window-system) in Doors.
2. Disconnect the electrical connector from the courtesy lamp.
3. Release the courtesy lamp by depressing the forward retainer.
4. Remove the courtesy lamp out of the front door trim panel, by pressing outward on the courtesy lamp and pulling out from the front of the door trim panel.
5. Rotate the lamp socket counterclockwise to release the socket from the lamp housing, then remove the socket.
6. Remove the bulb from the socket.

1. Install the bulb to the door courtesy lamp socket.
2. Install the lamp socket to the courtesy lamp housing, then rotate the socket clockwise.
3. Position the courtesy lamp to the front door trim panel.
4. Align the rear edge of the courtesy lamp retainer tab to the front door trim panel.
5. Install the courtesy lamp to the front door trim panel pressing the forward edge into place until the retainer is fully seated.
6. Connect the electrical connector from the courtesy lamp.
7. Install the front door trim panel. Refer to «Trim Panel Replacement - Side Front Door»(/buick/lacrosse/i-2004-2009/remont/door-locks-anti-theft-systems/#door-system-mirror-system-window-system) in Doors.

1. Remove 3 fasteners from the instrument panel (I/P) insulator.
2. Rotate the lamp socket counterclockwise. Remove the lamp socket from the insulator.
3. Remove the I/P courtesy lamp bulb from the socket.

1. Install the I/P courtesy lamp bulb to the socket.
2. Position the socket into the insulator opening. Rotate the socket clockwise to secure.
3. Align the insulator to the lower I/P.
4. Install 3 fasteners.

Scheme 24

Courtesy Lamp Replacement - Overhead Console

1. Open the instrument panel (I/P) compartment door.
2. Depress the retaining tabs on the top and bottom of the I/P compartment lamp switch.
3. Push the switch out of the opening.
4. Disconnect the electrical connector from the IP compartment lamp switch.
5. Remove the I/P compartment lamp switch.

1. Connect the electrical connector to the I/P compartment lamp switch.
2. Position the I/P compartment lamp switch to the opening. Press the switch into the opening.
3. Close the I/P compartment door.

1. Open the instrument panel (I/P) compartment door.
2. Depress the retaining tabs on the top and bottom of the I/P compartment lamp switch.
3. Push the switch out of the opening.
4. Pull the bulb from the switch.

1. Install the bulb to the I/P compartment lamp switch.
2. Press the switch into the opening.
3. Close the I/P compartment door.

1. Insert a flat-bladed tool at the rear end of the lens and pry out to remove the lens.
2. Remove the light bulb if necessary.
3. Insert a flat-bladed tool behind the lamp assembly at the switch end and pry that end out.
4. Disconnect the courtesy/reading lamp wiring harness from the socket.
5. Slide the lamp assembly out of the headliner.
6. Remove the lamp assembly from the vehicle.

1. Install the tab end of the lamp into the headliner.
2. Connect the wiring harness to the lamp.
3. Press the lamp into the headliner.
4. Install the lamp bulb if removed.
5. Position the tab end of the lens in the lamp and press in to install the lens.

1. Use a small flat-bladed tool to disengage the lamp lens. Remove the lens from the rearview mirror.
2. Carefully remove the bulb from the socket.

1. Install the bulb to the socket.
2. Align the lamp lens to the rearview mirror. Press the lens into place.

1. Lower the sunshade and open the illuminated mirror door.
2. Insert a small flat-bladed tool at the upper edge of the lamp lens. Carefully press down to remove the lens.
3. Remove the bulb.

1. Install the bulb.
2. Align the upper lens tab to the opening. Insert the upper edge of the lens.
3. Insert a small flat-bladed tool at the lower edge of the lamp lens. Carefully press up to install the lens.
4. Close the illuminated mirror door and raise the sunshade.

1. Remove the front floor console. Refer to «Console Replacement - Front Floor»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
2. Rotate the floor shift control indicator lamp socket (2). Pull the socket from the trim bezel.
3. Remove the bulb from the socket.

1. Install the bulb to the socket.
2. Position the floor shift control indicator lamp socket (2) into the trim bezel opening. Rotate the socket.
3. Install the front floor console. Refer to «Console Replacement - Front Floor»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.

Scheme 25

Headlamp Assembly or Headlamp Bulb Replacement

Headlamp Aiming

The vehicle has a visual optical headlamp aiming system. The aim has been preset at the factory and should need no further adjustment

However, If the vehicle is damaged in an accident, the headlamp aim may be affected and adjustment may be necessary.

If oncoming vehicles flash their high beams at you, this may also mean the vertical aim needs to be adjusted.

It is recommended that the vehicle is taken to your dealer for service if the headlamps need to be re-aimed. It is possible however, to re-aim the headlamps as described in the following procedure.

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's seat.
7. Tires should be properly inflated.

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

The vertical headlamp aiming screws are located under the hood near the headlamps.

The adjustment screw can be turned with a 6 mm male hex.

1. To adjust the vertical aim on the headlamps, do the following
2. Find the aim dot on the lens of the low-beam lamp.
3. Measure the distance from the ground to the aim dot on the lamp. Record the distance.
4. At the wall or other flat surface, measure from the ground upward the recorded distance from Step 2 and draw or tape a horizontal line the width of the vehicle.
5. Turn on the low-beam headlamps and place a piece of cardboard or equivalent in front of the headlamp not being aimed. This should allow only the beam of light from the headlamp being aimed to be seen on the flat surface.
6. Turn the vertical aiming screw until the headlamp beam is aimed to the horizontal tape line. The top edge of the cut-off should be positioned at the bottom edge of the horizontal tape line.
7. Repeat Steps 6 and 7 for the opposite headlamp.

Scheme 26

High Mounted Stop Lamp Replacement

Scheme 27

Roof Side Rail Lamp Replacement

1. Open the rear compartment.
2. Use a small flat-bladed tool to release the retaining tabs. Remove the rear compartment lamp.
3. Remove the bulb from the rear compartment lamp socket.

1. Install the bulb to the rear compartment lamp socket.
2. Install the rear compartment lamp, pressing into the lamp place until fully seated.
3. Close the rear compartment.

Exterior Lamps

The exterior lighting consist of the following lamps

1. Headlamps
2. Fog Lamps
3. Park Lamps
4. Tail Lamps
5. License Lamps
6. Marker Lamps
7. Turn Signal Lamps
8. Stop Lamps
9. Backup Lamps

Headlamps

You can use the headlamps two different ways.

1. Place the headlamp switch in the HEAD position for normal operations
2. Place the headlamp switch in the OFF position for automatic lamp control (ALC) operation. During ALC the low beam headlamps are ON for daytime running lamp (DRL) operation in daylight conditions at reduced intensity or low beam headlamps ON at full intensity with exterior park lamps ON in low light conditions.

The body control module (BCM) applies a pulse width modulated (PWM) voltage to the headlamp module and high beam relay in the underhood fuse block. The ground for the headlamp module is supplied from G113 or G115. For normal manual low beam operation when the headlamp switch is place in the HEAD position, ground from G202 is applied through the headlamp switch and to the BCM through the headlamp switch headlamps ON signal circuit. The BCM then applies a PWM voltage to the headlamp module/high beam relay voltage supply circuit. The headlamp module then applies battery positive voltage through the left front (LF) and right front (RF) LO Beam fuses to the left and right low beam headlamps. The ground for the left headlamps is supplied by G101 and the ground for the right headlamp is supplied by G100.

For high beam operation, ground is applied at all times to the headlamp dimmer switch from G202. When the headlamp dimmer switch is placed in the HIGH position, ground is then applied through the headlamp dimmer switch signal circuit to the BCM. The BCM then applies a ground to the headlamp high beam relay control circuit. This energizes the HI Beam relay, the relay then applies battery positive voltage through the LF and RF HI BEAM fuses to the LF and RF high beam headlamps. The ground for the left headlamps is supplied by G101 and the ground for the right headlamp is supplied by G100.

The BCM then sends a class 2 message to the instrument cluster in order to illuminate the high beam indicator lamp. If the headlamp switch is left in the HEAD position, the inadvertent power control feature will turn OFF the headlamps after 10 minutes after you turn the ignition switch to the OFF position. If you place the headlamp switch in the head position after the ignition switch has been turned OFF or if the ignition switch is in ACCY position, the headlamps will remain ON until you turn them OFF or until the battery runs dead.

HDLPS Suggested Indicator

If the park lamps are turned ON manually and the ambient light sensor detects a low light condition then the body control module (BCM) will send a class 2 message to the instrument panel cluster (IPC) to illuminate the HDLP suggested indicator.

Lights ON Warning

The body control module (BCM) activates the lights ON warning as requested by the headlamp dimmer switch. The lights ON warning sounds when the following occurs

1. The key is out of the ignition.
2. The BCM determines that the drivers door is open, signal is low.
3. The BCM determines that the headlamp switch is in the PARK or HEAD position.

Daytime Running Lamps (DRL)

The ambient light sensor is a light-sensitive transistor that varies its voltage signal to the body control module (BCM) in response to changes in the outside (ambient) light level. When the BCM receives this signal the BCM either turns ON the just the low beam headlamps at reduced intensity for the daytime running lamp (DRL) operation or turns ON the low beam headlamps and the exterior lamps for automatic lamp control (ALC). Any function or condition that turns ON the headlamps will cancel the DRL operation. Thirty seconds after you start the engine with the headlamp switch in the OFF position, the DRL will perform one of two actions

1. Illuminate the low beam headlamps at reduced intensity in daylight conditions
2. Illuminate the low beam headlamps and exterior park lamps for low light conditions

The DRL operates when the ignition switch is in the RUN position, the parking brake is not set and the transmission is not in the PARK position When these conditions are met and the DRL ambient light sensor indicates daylight conditions the DRL will illuminate

Fog Lamps

The FOG LPS fuse in the underhood fuse block supplies battery positive voltage to both the coil and switch side of the FOG LP Relay. When the fog lamp switch is placed in the ON position, ground is applied from G202 through the fog lamp switch to the body control module (BCM). The BCM then applies a ground to the fog lamp relay control circuit. This energizes the FOG LP relay and applies battery positive voltage through the fog lamp voltage supply circuit to the left and right fog lamps. Ground is applied at all times to the left fog lamp from G101 and to the right fog lamp from G100. The park lamps are headlamps must be ON in order for the fog lamps to illuminate. Fog lamp operation will be cancelled whenever the park lamps are turned OFF or the high beams are turned ON. When the park lamps are turned ON, the BCM sends a class 2 message to the instrument panel cluster (IPC) to illuminate the fog lamp indicator.

Park, Tail, Marker and License Lamps

The PK LAMPS fuse in the instrument panel (I/P) fuse block applies battery positive voltage to both the coil and switch side of the PARK LAMP Relay. When the headlamp switch is placed in either the HEAD or PARK position, ground is applied from G202 to the headlamp switch. The headlamp switch then applies the ground through the park lamp ON signal circuit to the body control module (BCM). The BCM then applies a ground to the park lamp relay enable circuit. This energizes the PK LAMP relay, applying battery positive voltage to all the park, tail marker and license lamps. The park, tail marker and license lamps are also turned ON when the headlamps are commanded ON by the BCM for low light operation.

Remote Keyless Entry Exterior Lamp Illumination

When the remote function actuation (RFA) module receives a door unlock command from the remote function actuator transmitter, the RFA module will ground the door unlock signal to the body control module (BCM), then send a class 2 signal to the BCM indicating that an UNLOCK command has been received. The BCM then will flash the park lamps twice. With all the doors closed and the remote keyless entry (RKE) transmitter is used to lock the doors the park lamps will flash twice. The park lamps will not flash if the rear compartment is opened using the RKE transmitter

Turn Signal Lamps

The TURN/HAZ fuse in the instrument panel (I/P) fuse block supplies battery positive voltage to the body control module (BCM) for the turn signal lamps and hazard lamps. When the turn signal switch is place in either the TURN LEFT or TURN RIGHT position, ground is applied from G202 through the turn signal switch to the BCM the BCM then applies battery positive voltage to the front and rear turn signal lamps supply voltage circuits. The left front turn signal lamp is grounded at G101 and the right front at G100. The left rear turn lamp is grounded at G301 and the right rear at G302.

Turn Signal Reminder

The body control module (BCM) activates the turn signal warning as requested by either turn signal switch. The turn signal warning sounds when the following occurs

1. The ignition is in the RUN position.
2. The turn signal switch is in either turn position, sensing, within one second, an open to battery positive voltage transition in the turn signal control circuit, left or right turn.
3. The vehicle has traveled a distance of 1.2 km (0.75 mi) by counting pulses ON the vehicle speed input circuit.

The BCM turns OFF the turn signal reminder when either the ignition switch is turned to the OFF position or the turn signal switch returns to the OFF position.

Hazard Lamps

The TURN/HAZ fuse in the instrument panel (I/P) fuse block supplies battery positive voltage to the body control module (BCM) for the turn signal lamps and hazard lamps. When the hazard switch is placed in to the ON position, the driver information center (DIC) sends a signal to the BCM through he hazard switch signal circuit. The BCM then flashes all of the turn signal lamps ON and OFF.

Stop Lamps

The rear turn signal lamps are also used as the stop lamps. The TURN/HAZ fuse in the instrument panel (I/P) fuse block supplies battery positive voltage to the body control module (BCM) for the turn signal/stop lamps and hazard lamps. The CHMSL/BKUP fuse in the I/P fuse block provides battery positive voltage to the center high mounted stop lamp (CHMSL). The brake pedal position sensor receives a low reference signal and a 10-volt reference signal from the BCM. Whenever the brake pedal is applied, the brake pedal position sensor applies a variable voltage signal to the BCM through the stop lamp switch signal circuit. The BCM then applies battery positive voltage to the rear turn/stop lamps and to the CHMSL, illuminating them. The left rear turn lamp is grounded at G301 and the right rear stop/turn lamp and CHMSL is grounded at G302.

Backup Lamps

The CHMSL/BKUP fuse in the instrument panel (I/P) fuse block supplies battery positive voltage to the body control module (BCM). When the driver places the gear selector in to the REVERSE position, the powertrain control module (PCM) sends a class 2 message to the BCM. The BCM then applies battery positive voltage to the backup lamp supply voltage circuit. The left backup lamp is grounded at G301 and the right backup lamp is grounded at G302.

Battery Rundown Protection/Inadvertent Power

The body control module (BCM) used in this vehicle controls the lighting system through circuits that enable both the exterior lamp functions of park, head and fog lamps as well as the interior lamps. The BCM opens these enabling circuits 20 minutes 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 20 minute period the timer will reset for another 20 minutes.

Interior Lighting

The interior lighting consist of lamps that may not be dimmed (Interior Lamps) and lamps that may be dimmed (Interior Lamps Dimming).

Interior Lamps

The first group of lamps are the interior courtesy lamps that may not be dimmed manually, these include

1. The dome lamp
2. The instrument panel (I/P) compartment lamp
3. The I/P courtesy lamps
4. The rear compartment lamp
5. The roof rail courtesy/reading lamps
6. The sunshade vanity mirror lamps

Interior Lamps Features

The interior lamps system features the following functions

1. An illuminated entry feature that illuminates the courtesy lamps when entering the vehicle or activating the remote keyless entry system.
2. An illuminated exit feature that illuminates the courtesy lamps when the ignition key has been removed from the ignition.
3. An inadvertent power feature that supplies voltage to all interior lamps after the ignition is turned OFF. The inadvertent power feature will deactivate all interior lamps after 20 minutes to prevent battery rundown.
4. A theater dimming feature that will slowly dim the interior lamps from full brightness to OFF.
5. An lamp switch assembly that illuminates the courtesy lamps.
6. Individual switches for control of each interior lamp that is not illuminate with the interior lamp switch.

Courtesy/Illuminated Entry Lamps

When the body control module (BCM) is in an active state (awake) it energizes the courtesy lamps supply voltage circuit. The courtesy lamps supply voltage circuit supplies voltage to all of the interior lamps, including the illuminated entry lamps (courtesy lamps). The illuminated entry lamps are turned ON when they receive a battery positive voltage from the courtesy lamp supply voltage circuit of the BCM. When the ignition is in the LOCK position the BCM will apply the courtesy lamp supply voltage circuit under the following conditions

1. The door jamb input transitions to an active state (opening a door).
2. The use of the remote keyless entry (RKE) to unlock the side doors.

When the courtesy lamps supply voltage circuit and the courtesy lamp low control circuit are active the courtesy/illuminated entry lamps will illuminate. The courtesy lamps/illuminated entry lamps include the following interior lamps

1. The dome lamp
2. The roof rail courtesy lamps
3. The I/P courtesy lamps

When the driver uses the remote function actuator transmitter to unlock the doors, the BCM will illuminate the courtesy lamps for approximately 40 seconds, unless another BCM function causes the lamps to remain active. If the ignition switch is turned to either the RUN or START position the courtesy lamps will turn OFF immediately.

When the door latch switch signal circuit is active with the ignition in the OFF position the BCM will illuminate the courtesy lamps. The courtesy lamps will remain illuminated for approximately 25 seconds, after the door latch switch signal circuit becomes inactive, unless another BCM function causes the lamps to remain active. If the ignition switch is turned to either the RUN or START position the courtesy lamps will turn OFF immediately.

Courtesy/Illuminated Exit

The illuminated exit feature will activate the courtesy lamps when the key IN input of the BCM transitions from an active state to an inactive state (removing the ignition key). When the key is removed from the ignition, the key IN input to the BCM becomes inactive. The BCM will illuminate the courtesy lamps for approximately 25 seconds, unless another BCM function causes the lamps to remain active.

Inadvertent Power Feature

Inadvertent power feature provides a similar function for the interior lamps as a retained accessory power feature. The BCM will energize the courtesy lamps supply voltage circuit when the BCM is in the active state (awake). When the courtesy lamps supply voltage circuit is energized, it supplies voltage to all the interior lights. The BCM will continue to supply voltage to the interior lamps after the ignition is turned OFF so that the interior lamps may be operated.

The inadvertent power feature will also act as battery run down protection by deactivate the courtesy lamps supply voltage circuit after 20 minutes once the BCM becomes inactive, ignition OFF and no BCM input activity.

Theater Dimming

The theater dimming feature that will slowly dim the interior lamps from full brightness to OFF. The following actions will over ride the theater dimming feature causing the courtesy lamps to deactivate immediately if no other BCM function commands the courtesy lamps ON

1. A transition from active to inactive of the interior lamps switch, turning OFF the interior lamps switch
2. A LOCK command from the remote keyless entry system
3. A last door closed locking function, locking and closing all the doors

Courtesy Lamps Manual Operation

The courtesy lamps, may be manually operated by the lamp switch assembly. When the dimmer switch is placed in the DOME position the BCM receives a ground from the courtesy lamp switch signal circuit. Upon receiving the courtesy lamp switch signal the BCM then applies battery positive voltage to the courtesy lamp supply voltage circuit, which illuminates the courtesy lamps. The voltage for all interior lamps is supplied by the courtesy lamp supply voltage circuit of the BCM, whenever the BCM is active. The interior lamp switch will override any BCM operation of the interior lamps, such as entry illumination.

Dome Lamp

The dome lamp is turned ON by the lamp switch assembly or during illuminated entry.

During illuminated entry or when the lamp switch assembly is in the DOME position, the body control module (BCM) wakes up and then energizes the courtesy lamps supply voltage circuit, suppling voltage to all interior lamps.

I/P Compartment Lamp

When the I/P compartment is opened the I/P compartment lamp illuminates, if the courtesy lamps supply voltage circuit of the BCM is activated, BCM awake.

The I/P compartment lamp illuminates when the courtesy lamps supply circuit of the BCM supplies voltage to the I/P compartment lamp and the I/P compartment switch closes, providing a ground path.

I/P Courtesy Lamp

The I/P courtesy lamp is turned ON by the lamp switch assembly or during illuminated entry.

During illuminated entry or when the I/P dimmer switch is DOME the BCM wakes up and then energizes the courtesy lamps supply voltage circuit, suppling voltage to all interior lamps.

Rear Compartment Lamp

When the rear compartment is opened, the rear compartment lamp illuminates.

When the rear compartment is opened, the rear compartment courtesy lamp switch sends a ground signal to the BCM, waking the BCM. When the BCM wakes up it will then energize the courtesy lamps supply voltage circuit, suppling voltage to the rear compartment courtesy lamp. The rear compartment courtesy lamp switch will provide a ground path for the rear compartment courtesy lamp in order to illuminate the lamp.

Roof Rail Courtesy/Reading Lamps

The roof rail courtesy lamps are turned ON by the lamp switch assembly, the individual roof rail courtesy lamp switch or during illuminated entry.

During illuminated entry or when the I/P dimmer switch is ON the BCM wakes up and then energizes the courtesy lamps supply voltage circuit, suppling voltage to all interior lamps.

The roof rail courtesy/reading lamps can be turned ON from the individual roof rail courtesy lamp switch. The BCM supplies voltage through the courtesy lamps supply voltage circuit when the BCM is awake. Manually turning ON the roof rail courtesy lamp switch provides a ground path.

Sunshade Vanity Mirror Lamps

When the vanity mirror cover on the sunshade is opened, the sunshade mirror lamp illuminates.

The sunshade mirror lamps receive voltage from the courtesy lamps supply voltage circuit anytime the BCM is awake. The sunshade illuminated mirror lamps receive ground from their individual switches when the sunshade is open.

Interior Lamps Dimming

The second group of lamps include lamps which may be dimmed. This group uses a combination of class 2 dimming and incandescent lamps.

1. The PRNDL lamp
2. The door switches and window switches
3. The HVAC control head assembly
4. The outside rearview mirror switches
5. The driver information center (DIC)
6. The radio
7. The lamp switch assembly
8. The steering wheel controls
9. The instrument panel cluster (IPC)
10. The traction control switch

When the headlamp switch is placed in the PARK position, ground is supplied through the headlamp switch to body control module (BCM). The BCM also applies a voltage reference and a low reference signal to the interior lamp dimmer switch. When the interior lamp switch is varied, the position of the switch is applied through the instrument panel (I/P) dimming control circuit to the BCM. The BCM then applies a voltage to the interior lamps.

The lamps become illuminated when the park lamps are ON. The brightness of all the incandescent lamps is determined by a variable voltage signal from the dimmer switch and sent through the instrument panel lamp supply voltage circuit. The lamps are located in various components (see schematics).

Incandescent Dimming

The incandescent lamps become illuminated when the park lamps are on. The brightness of all the incandescent lamps is determined by a variable voltage signal from the dimmer switch and sent through the instrument panel lamp supply voltage circuit. The incandescent lamps are located in various components (see schematics).

Driver Controls and Modules

The BCM module processes the inputs and the controls. The ambient light sensor supplies the BCM with a signal for daytime conditions or for low light conditions

1. The BCM
2. The DIC
3. The IPC

Driver controls include the following components

1. The I/P dimmer switch
2. The door jamb switches
3. The headlamp switch
4. The rear compartment lid ajar switch
5. The roof rail courtesy reading lamp switch
6. The sunshade vanity mirror lamps switch
7. The I/P compartment lamp switch

See also:
• SIR DISABLING AND ENABLING ZONES
• Diagnostic System Check - Vehicle
• Testing for Intermittent Conditions and Poor Connections
• Master Electrical Component List
• Circuit Testing
• Wiring Repairs
• Control Module References
• Connector Repairs
• Computer/Integrating Systems Connector End Views
• Sun Load Sensor Replacement
• Checking Aftermarket Accessories
• Lock Replacement - Front Door
• Power and Grounding Connector End Views
• Driver Information Center Switch Replacement
• Multifunction, Turn Signal Switch Replacement
• Symptoms - Keyless Entry
• Rear Compartment Lid Ajar Switch Replacement
• Testing for Electrical Intermittents
• Sunshade Replacement
• Fastener Notice
• Halogen Bulb Caution
• Fender, Fender Insulator, Wheelhouse Liner Replacement - Front
• Fastener Tightening Specifications
• Seat Cushion Replacement - Rear
• DTC B2525
• Brake Pedal Position Sensor Calibration
• Brake Pedal Position Sensor Replacement
• Backup Lamps Always On
• Backup Lamps Inoperative
• Courtesy Lamps Always On
• Courtesy Lamps Inoperative
• Daytime Running Lamps (DRL) Inoperative
• Fog Lamps Always On
• Fog Lamps Inoperative
• Hazard Lamps Always On
• Hazard Lamps Inoperative
• Headlamps Always On - Low or High Beam
• Headlamps Inoperative - High Beams
• Headlamps Inoperative - Low Beams
• Headlamps Inoperative - Flash to Pass
• Illuminated Entry Lamps Inoperative
• Interior Backlighting Does Not Dim
• Interior Backlighting Inoperative
• Instrument Panel (I/P) Compartment Lamp Inoperative
• Instrument Panel (I/P) Compartment Lamp Always On
• Park, License and Tail Lamps Always On
• Park, License and Tail Lamps Inoperative
• Reading Lamp(s) Always On
• Reading Lamp(s) Inoperative
• Rear Compartment Lamp(s) Always On
• Rear Compartment Lamp(s) Inoperative
• Stop Lamps Always On
• Stop Lamps Inoperative
• Turn Signal Lamps and/or Indicators Always On or Flashing
• Turn Signal Lamps and/or Indicators Inoperative
• Vanity Mirror Lamp(s) Always On
• Vanity Mirror Lamp(s) Inoperative
• Fastener Tightening Specifications