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Contents Wiring diagrams Section: Entertainment Systems All sections

Cellular System, Entertainment System, and Navigation System Buick LaCrosse II

Entertainment Systems 51 illustrations ~39701 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Radio Antenna Coil Fastener8 N.m70 lb in
Radio Antenna Module Fastener9 N.m80 lb in
Video Display Fastener9.5 N.m84 lb in

Fastener Tightening Specifications

Scheme 1

Scheme 1: Power, Ground, Antennas And Serial Data
Scheme 1: Power, Ground, Antennas And Serial Data

Scheme 2

Scheme 2: Amplifier (UQA)
Scheme 2: Amplifier (UQA)

Scheme 3

Scheme 3: Amplifier (UQA With UYS Or UWG)
Scheme 3: Amplifier (UQA With UYS Or UWG)

Scheme 4

Scheme 4: Speakers (UQA)
Scheme 4: Speakers (UQA)

Scheme 5

Scheme 5: Speakers (U65)
Scheme 5: Speakers (U65)

Scheme 6

Scheme 6: Display (Without UYS)
Scheme 6: Display (Without UYS)

Scheme 7

Scheme 7: Navigation System (UYS)
Scheme 7: Navigation System (UYS)

Scheme 8

Scheme 8: USB Interface (USR Without KTA)
Scheme 8: USB Interface (USR Without KTA)

Scheme 9

Scheme 9: USB Interface (KTA)
Scheme 9: USB Interface (KTA)

Scheme 10

Scheme 10: UE1
Scheme 10: UE1

Scheme 11

Scheme 11: Display Power And Ground
Scheme 11: Display Power And Ground

Scheme 12

Scheme 12: Video Signals
Scheme 12: Video Signals

Scheme 13

Scheme 13: Audio Signals
Scheme 13: Audio Signals

Diagnostic Code Index

DTCDescription
DTC B0000DTC B0000 5A Vehicle Speed Information Circuit Not Plausible
DTC B1020DTC B1020 00 Auxiliary Electronic Control Unit (ECU) Performance
DTC B1025, B1035, B1045, or B1055DTC B1025 01 Left Front Audio Output Circuit Short to Battery DTC B1025 02 Left Front Audio Output Circuit Short to Ground DTC B1025 04 Left Front Audio Output Circuit Open DTC B1035 01 Front Audio Output Circuit Short to Battery DTC B1035 02 Right Front Audio Output Circuit Short to Ground DTC B1035 04 Right Front Audio Output Circuit Open DTC B1045 01 Left Rear Audio Output Circuit Short to Battery DTC B1045 02 Left Rear Audio Output Circuit Short to Ground DTC B1045 04 Left Rear Audio Output Circuit Open DTC B1055 01 Right Rear Audio Output Circuit Short to Battery DTC B1055 02 Right Rear Audio Output Circuit Short to Ground DTC B1055 04 Right Rear Audio Output Circuit Open
DTC B125ADTC B125A 02 Antenna Signal Circuit Short to Ground DTC B125A 04 Antenna Signal Circuit Open Circuit
DTC B125CDTC B125C 01 Satellite Antenna Circuit Short to Battery DTC B125C 02 Satellite Antenna Circuit Short to Ground DTC B125C 04 Satellite Antenna Circuit Open
DTC B1265DTC B1265 02 Switched 14 Volt Performance Short to Ground
DTC B1271DTC B1271 00 Theft Protection Active
DTC B1278 or B1279DTC B1278 01 Left Auxiliary Input Signal Circuit Short to Battery DTC B1278 02 Left Auxiliary Input Signal Circuit Short to Ground DTC B1279 01 Right Auxiliary Input Signal Circuit Short to Battery DTC B1279 02 Right Auxiliary Input Signal Circuit Short to Ground
DTC B1287DTC B1287 01 Amplifier Control Signal Circuit Short to Battery DTC B1287 02 Amplifier Control Signal Circuit Short to Ground DTC B1287 04 Amplifier Control Signal Circuit Open
DTC B1288DTC B1288 01 Video Display Mode Control Signal Short to Battery DTC B1288 02 Video Display Mode Control Signal Short to Ground DTC B1288 04 Video Display Mode Control Signal Open Circuit
DTC B1289DTC B1289 01 Video Display Brightness Control Signal Short to Battery DTC B1289 02 Video Display Brightness Control Signal Short to Ground DTC B1289 04 Video Display Brightness Control Signal Open Circuit
DTC B1446 or B1447DTC B1446 03 Replace Backup Power Source Voltage Below Threshold DTC B1447 04 Backup Power Source Open Circuit
DTC B2455DTC B2455 02 Cellular Phone Microphone Circuit Short to Ground DTC B2455 04 Cellular Phone Microphone Circuit Open
DTC B2462DTC B2462 01 Global Positioning System Short to Battery DTC B2462 02 Global Positioning System Short to Ground DTC B2462 04 Global Positioning System Open
DTC B2470DTC B2470 02 Cellular Phone Antenna Circuit Malfunction Short to Ground DTC B2470 04 Cellular Phone Antenna Circuit Malfunction Open Circuit
DTC B2476 or B2482DTC B2476 04 Cellular Phone Select Service Switch Open DTC B2476 59 Cellular Phone Select Service Switch Protection Time-out DTC B2482 00 Cellular Phone Select Service Switch Range/Performance
DTC B2485DTC B2485 02 Wireless Communication (BT) Antenna Circuit Short to Ground DTC B2485 04 Wireless Communication (BT) Antenna Circuit Open

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Vehicle Speed Signal CircuitB0000 5AB0000 5AB0000 5AB0000 5A

Circuit/System Description

The radio receives a vehicle speed signal from the electronic brake control module in order to correlate actual vehicle speed to the movement of the vehicle calculated by the navigation system and reported serial data.

Conditions for Running the DTC

  1. Radio ON.
  2. Battery voltage must be between 9-16 V.

Conditions for Setting the DTC

  1. Vehicle speed from serial data is more than 5 km/h (3 mph) and vehicle speed pulse from the electronic brake control module is 0 km/h (0 mph).
  2. Vehicle speed calculated from the navigation processing software is more than 36 km/h (22 mph) and vehicle speed pulse from the electronic brake control module is 0 km/h (0 mph) for 10 seconds continuously.

Action Taken When the DTC Sets

  1. Turn by turn route navigation may be inoperative.
  2. Vehicle indicated location may be inaccurate.

Conditions for Clearing the DTC

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC clears after 100 malfunction-free ignition cycles.

Reference Information

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

Note. Diagnose any antilock brake system (ABS) related DTCs before performing this diagnostic.

  1. Ignition OFF, disconnect the X3 harness connector at the A11 radio.
  2. Ignition ON.
  3. Test for less than 1 V between the signal circuit terminal 20 and ground. If 1 V or greater Ignition OFF, disconnect the harness connector at the K17 electronic brake control module. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K17 electronic brake control module. If less than 1 V
  4. Test for 3-7 Hz between the signal circuit terminal 20 and ground while operating the vehicle drive wheels at 5 mph (8 km/h). If not 3-7 Hz Ignition OFF, disconnect the harness connector at the K17 electronic brake control module. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 electronic brake control module. If 3-7 Hz
  5. Test or replace the A11 radio.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio or electronic brake control module replacement, programming, and setup.

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The radio communicates with the radio controls via serial data. This DTC indicates a fault in the radio controls. No external circuits are involved. The radio may continue to respond normally to faceplate functions when this DTC is set.

  1. Ignition is ON or in the ACC position.
  2. The system voltage is at least 9.5 V and no more than 15.5 V.
  3. All the above conditions are present for greater than 10 seconds.

The radio receives an improper status response indicating an internal ECU fault in the radio controls.

No action is taken.

  1. A current DTC clears when the radio receives a proper status response message back from the radio control assembly.
  2. A history DTC clears after 50 malfunction-free ignition cycles.

Diagnostic Aids

  1. This DTC may be stored as a history DTC without affecting the operation of the radio controls.
  2. If stored only as a history DTC and not retrieved as a current DTC, do not replace the radio controls.
  3. If this DTC is retrieved as both a current and history DTC, replace the radio controls.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Ignition ON.
  2. Verify DTC B1020 is not set. If DTC B1020 is set Replace the A22 radio controls. If DTC B1020 is not set
  3. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio controls replacement, programming, and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Front Audio Signal CircuitB1025 02*B1025 04**B1025 01*
Right Front Audio Signal CircuitB1035 02*B1035 04**B1035 01*
Left Rear Audio Signal CircuitB1045 02*B1045 04**B1045 01*
Right Rear Audio Signal CircuitB1055 02*B1055 04**B1055 01*
* Noticeable audio distortion possible. ** No or reduced sound from speaker.

Each of the audio output channel circuits (+) and (-), at the radio and audio amplifier have a DC bias voltage that is approximately one half of battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5 V DC. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound. The frequency (Hz) of the AC voltage signal is directly related to the frequency of the input (audio source playing) to the audio system. Both the DC bias voltage and the AC voltage signals are needed for the audio system to properly produce sound.

  1. Ignition is ON or in the ACC position
  2. The system voltage is 9-16 V
  3. The test is run once during radio wake up

B1025 01, B1035 01, B1045 01, B1055 01

The radio detects a short to voltage on the specified audio (+) or (-) circuit.

B1025 02, B1035 02, B1045 02, B1055 02

The radio detects a short to ground on the specified audio (+) or (-) circuit.

B1025 04, B1035 04, B1045 04, B1055 04

The radio detects an open on the specified audio (+) or (-) circuit.

The radio continues to send the output signal to the speaker signal circuit with the current fault.

  1. A current DTC clears when the conditions for setting the DTC are no longer present and the ignition has been cycled from OFF to ON.
  2. A history DTC clears after 50 malfunction-free ignition cycles.
  1. Improper speaker mounting or loose trim may cause an audible buzz or distortion. Inspect the appropriate speaker and the surrounding interior trim for proper and secure mounting. If the speaker or surrounding interior trim is found to be loose or improperly secured, correctly secure the item.
  2. When equipped with an amplifier, the radio does not set DTCs for the audio outputs.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, A11 radio ON, mute OFF.
  2. Verify clear audio is heard from each speaker, adjusting fade and balance controls to test each speaker individually. If audio is inoperative from one or more speakers, or the audio emitted is not clear. Refer to Circuit/System Testing below. If clear audio is heard from all speakers.
  3. All OK.
  1. Ignition OFF, disconnect the harness connector at the appropriate P19 speaker. Ignition ON, A11 radio ON, mute OFF.
  2. Test for 5-7 V between each audio signal circuit terminal 1 and terminal 2 and ground. If less than 5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If greater than 7 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If between 5-7 V
  3. Test or replace the P19 speaker.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Speaker Replacement Reference»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__speaker-replacement-reference)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Radio Antenna CoaxB125A 02B125A 041
Antenna Module Ground1
1. May exhibit possible AM/FM interference.

The antenna module receives both AM and FM signals from the rear glass antenna. The radio antenna module is enabled when the radio is turned on. The radio provides battery voltage to the antenna module using the center conductor of the antenna coaxial cable. When a 12 V signal is seen by the module on the center conductor of the antenna coax, both AM and FM signals are amplified.

  1. Ignition ON.
  2. Battery voltage must be between 9-16 V.

B125A 02

The radio detects a short to ground in the antenna signal circuit center conductor.

B125A 04

The radio detects an open in the antenna signal circuit center conductor.

Radio reception may be poor or not available.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clears after 50 consecutive malfunction-free ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, A11 radio ON, tune to a strong AM or FM station. Verify that the AM or FM reception is clear.

  1. Ignition OFF, disconnect the radio antenna coax from the A11 radio and from the K46 radio antenna module.
  2. Test for infinite resistance between the antenna coax center terminal and ground. If less than the specified value, replace the antenna coax.
  3. Test for less than 5 ohms on the antenna coax center circuit from end to end. If greater than the specified range, replace the antenna coax.
  4. Ignition ON, test for less than 1 V between the antenna coax center terminal and ground. If greater than the specified range, replace the antenna coax.
  5. Test for infinite resistance between the coax center terminal and the outer shield. If less than the specified value, replace the antenna coax.
  6. Connect the antenna coax to the A11 radio. Test for 12-15 V between the antenna coax center terminal and ground at the K46 radio antenna module connector. If not within the specified range, replace the A11 radio.
  7. If all circuits test normal, replace the K46 radio antenna module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for radio replacement, setup, and programming

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The digital radio receiver, located inside the radio, receives digital radio information from the digital radio antenna located on the outside of the vehicle. The digital radio receiver is connected to the digital radio antenna via a shielded coax cable. The digital radio antenna contains an amplifier which is powered by the radio through the coax cable.

This DTC is run every 300 milliseconds.

The radio detects a circuit fault in the digital radio antenna.

The radio displays No XM Signal or Check Antenna.

  1. A current DTC clears when the condition for setting the DTC is no longer present.
  2. A history DTC clears after 100 malfunction-free ignition cycles.

The digital radio antenna requires a clear line of sight to the sky to operate properly. Reception may be limited, intermittent, or unavailable inside structures.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Special Tools

EL-48028 Digital Radio Test Antenna

  1. With the vehicle outside in an area with an unobstructed view of the southern sky, tune to XM.
  2. Verify DTC B125C is not set as current and the No XM Signal message is not displayed on the radio. If DTC B125C is set as current or the No XM Signal message is displayed. Refer to Circuit/System Testing below. If DTC B125C is not set as current and the No XM Signal message is not displayed.
  3. All OK.
  1. Ignition OFF, disconnect the digital radio antenna coax cable from the A11 radio. Connect the EL-48028 Digital Radio Test Antenna to the radio and place on the roof of the vehicle.
  2. Ignition ON, radio tuned to XM channel 1.
  3. Verify DTC B125C is not set as current and XM reception is improved. If DTC B125C is set as current or XM reception is not improved Replace the A11 radio. If DTC B125C is not set as current and XM reception is improved
  4. Ignition OFF, disconnect the digital radio antenna coax cable from the T4G cellular phone, navigation, and digital radio antenna.
  5. Verify the digital radio antenna coax cable passes the coax cable component test. Refer to Component Testing below. If the coax cable does not pass the test Replace the antenna coax cable If the coax cable passes the test
  6. Test or replace the T4G cellular phone, navigation, and digital radio antenna.

Component Testing

CAUTIONRefer to Test Probe Caution .

Note. Before testing the coax cable, check the cable exterior for being pinched, cut, damaged, or having loose connections at the components, which can cause reception issues. To prevent false reading when testing the center coax terminals, use care not to ground the test probe on the outer housing/shield.

Coax Cable Test

  1. Ignition OFF, disconnect the coax cable at both components.
  2. Test for less than 5 ohms between coax cable center terminal end to end. If 5 ohms or greater Replace the coax cable If less than 5 ohms
  3. Test for less than 5 ohms between the coax cable outer shield end to end. If 5 ohms or greater Replace the coax cable If less than 5 ohms
  4. Test for infinite resistance between the coax cable center terminal and the coax cable outer shield. If less than infinite resistance Replace the coax cable If infinite resistance
  5. All OK

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Radio Antenna Base Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Remote EnableDTC B1265 0 ******
* all components requiring remote enable inoperative ** fault may affect one or more components, dependant on fault location and vehicle equipment *** components will not power off with infotainment system

When the radio is on, a discrete 12 V signal is supplied on the entertainment remote enable circuit to the Audio Amplifier, Color Info Display Module (if equipped), and the Seatback Video Displays (if equipped). This signal is used to control the power state of the components.

The following are conditions that must be present in order for the radio to enable diagnostics

  1. The radio is ON.
  2. The system voltage is 9 -16 V
  1. The radio detects a short to ground on the entertainment remote enable circuit circuit.
  2. The above condition is present for greater than 250 mS.
  1. The radio implements a current limiting mode and disables the output on the entertainment remote enable circuit.
  2. All components connected on the entertainment remote enable circuit will be inoperative.
  1. The condition for setting the DTC no longer exists.
  2. After the ignition has been OFF for a sufficient amount of time to allow the radio to enter a low power/sleep state, the radio will re-enable the output on the following ignition cycle and the DTC will become history.
  3. A history DTC clears after 50 malfunction-free ignition cycles.
  1. This DTC may be stored as a history DTC without affecting the operation of the radio/infotainment systems.
  2. The radio's current limiting logic will not re-enable the output on the entertainment remote enable circuit until after the radio performs a full power-down. It may be necessary to wait 5 minutes between each test attempt with the key OFF and retained accessory power OFF.

Schematic Reference

  1. «Radio/Navigation System Schematics»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Video System Schematics»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition OFF, radio OFF, radio B+ fuse removed. Disconnect all of the harness connectors listed below: T3 Audio Amplifier X3 P17 Color Information Display Module X1 (if equipped) P22E Driver Seatback Video Display (if equipped) P22F Passenger Seatback Video Display (if equipped)
  2. Install the radio B+ fuse. Ignition ON, A11 radio ON.
  3. Verify that a test lamp illuminates between the control circuit terminals listed below and ground: T3 Audio Amplifier X3 terminal 13 P17 Color Information Display Module X1 terminal 6 (if equipped) P22E Driver Seatback Video Display terminal 2 (if equipped) P22F Passenger Seatback Video Display terminal 2 (if equipped) If the test lamp does not illuminate. Ignition OFF. Disconnect the X1 harness at the A11 radio. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance. Test for less than 2 ohms in the control circuit end to end. If greater than 2 ohms, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If the test lamp illuminates.
  4. Verify that DTC B1265 does NOT set as each component is connected one at a time. If DTC B1265 sets. Replace the module/component that was just connected If DTC B1265 does not set.
  5. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Video Display Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Driver Information Display Replacement (With UAG)»(/buick/lacrosse/ii-2009-2013/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges) , «Driver Information Display Replacement (With UDT)»(/buick/lacrosse/ii-2009-2013/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
  3. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio and amplifier replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the radio is initially installed in the vehicle, the radio receives VIN information via serial data. The radio stores a portion of the VIN and compares this sequence to the VIN information received each time the radio powers on. The VIN in the radio is a single one-time learn.

The radio theft deterrent system is intended to disable or limit radio functionality if incorrect vehicle information is received by the radio. The radio disables functionality if the VIN information received by the radio does not match the VIN information that has been learned by the radio. This DTC is generated by the module when the Theft Protection is activated.

This DTC test runs when the radio changes from OFF to ON.

The radio has learned a correct VIN sequence and the VIN information received via serial data does NOT match the learned VIN sequence.

  1. The radio may be disabled or have limited functionality.
  2. The radio display will indicate that theft protection is active.

The radio receives the correct VIN information via serial data.

A possible cause of incorrect VIN info could be the radio was originally installed in another vehicle.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, radio ON.
  2. Verify DTC B1271 is not set. If DTC B1271 is set Replace the A11 radio. If DTC B1271 is not set
  3. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio replacement, programming, and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
B+4
Detection Signal Circuit455
Left Audio Signal Terminal 12B1278 02, 33B1278 01, 3
Left Audio Signal Terminal 14333
Right Audio Signal Terminal 13B1279 02, 22B1279 01, 2
Right Audio Signal Terminal 15222
Audio Common Circuit1
Ground4
1. No or distorted audio from both sides 2. No or distorted right side audio 3. No or distorted left side audio 4. External audio inputs inoperative 5. AUX selection always available with or without device connected

A remote 3.5 mm auxiliary stereo jack allows playback of audio signals from remote devices (e.g., laptop computer, IPOD, MP3 player, etc.). The auxiliary audio jack has an internal mechanical detection switch. The switch is normally closed, connecting the detection circuit to the audio common circuit. When a device is inserted to the auxiliary audio jack, the switch opens and the multimedia player interface module detects a high voltage on the detection circuit. A serial data message is sent to the radio, the radio will switch to AUX as the audio source. The multimedia player interface module receives the analog audio signals from the connected device and sends the signals to the radio.

  1. Ignition in RUN or ACC position.
  2. The system voltage is at least 9.5 V and no more than 15.5 V.
  3. The multimedia player interface module detects a device has been connected to the auxiliary audio input jack.

B1278 01, B1279 01

  1. The multimedia player interface module detects a short to battery on either of the audio signal circuits from the auxiliary audio jack.
  2. The condition is present for greater than 250 mS.

B1278 02, B1279 02

  1. The multimedia player interface module detects a short to ground on either of the audio signal circuits from the auxiliary audio jack.
  2. The condition is present for greater than 250 mS.

No or reduced audio is heard from the remote audio device.

  1. The conditions for setting the DTC are no longer present on the auxiliary input signal circuits.
  2. A history DTC clears after 50 malfunction-free ignition cycles.
  1. Playback of an audio device that is connected to the 3.5 mm jack can only be controlled using the controls on the device.
  2. The volume control on the device may need to be adjusted to ensure sufficient playback volume through the infotainment system.
  3. This DTC may be stored as a history DTC without affecting the operation of the module.
  4. If stored only as a history DTC and not retrieved as a current DTC, do not replace the module.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#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 harness connector at the X83 auxiliary audio input.
  2. Ignition ON, test for less than 1 V between the terminals listed below and ground: Signal terminal 1 Signal terminal 2 If greater than the specified value, test the circuit for a short to voltage. If the circuit tests normal, replace the T11 multimedia player interface module.
  3. Ignition OFF, test for infinite resistance between the terminals listed below and ground: Signal terminal 1 Signal terminal 2 If less than the specified value, test the circuit for a short to ground. If the circuit tests normal, replace the T11 multimedia player interface module.
  4. If all of the circuits test normal, replace the X83 auxiliary audio input.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References multimedia player interface module replacement, setup, and programming

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Amplifier ControlDTC B1287 02,**DTC B1287 04,**DTC B1287 01,*
* No audio output. ** 4 Channel unmute, possible noise in speakers when radio muted or turned off

The radio amplifier control circuit provides varying pulse width modulated (PWM) signals to control overall muting of the amplifier. The PWM signals are varying duty cycle percentages ranging from 0-100 percent. A low duty cycle unmutes all amplifier channels and a high duty cycle mutes all amplifier channels. The amplifier control circuit will measure less than 1 V when the mute function is OFF, and approximately 8 V DC when at full mute. The radio monitors the amp control circuit for faults.

The following are conditions that must be present in order for the radio to enable the diagnostics.

  1. The radio is in ACCESSORY, RUN, or RAP power mode.
  2. The system voltage is 9-16 V.
  3. The radio performs the test once during wake up.

The radio detects a fault on the amplifier control circuit 400 ms after radio activates the remote enable circuit.

Radio sets the DTC and continues to output correct state.

  1. The condition must be corrected.
  2. A history DTC clears after 100 malfunction-free ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#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 X3 harness connector at the T3 amplifier. Ignition ON, A11 radio ON, mute ON.
  2. Test for 7.5-8.5 V between the control circuit terminal 6 and ground. If greater than 8.5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If less than 7.5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If between 7.5-8.5 V
  3. A11 radio ON, mute OFF.
  4. Test for less than 1 V between the control circuit terminal 6 and ground. If 1 V or greater Replace the A11 radio. If less than 1 V
  5. Test or replace the T3 amplifier.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio and amplifier replacement, programming, and setup.

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Video Display B+21
Remote Enable Control CircuitB1265 02, 345
DVD Audio Common Signal (-)666
Left DVD Audio Signal (+)777
Right DVD Audio Signal (+)888
DVD Video Signal (+)997
DVD Video Signal (-)999, 10
Infrared Remote Signal (+)111111
Infrared Remote Signal (-)111111
Video Mode SignalB1288 02, 12B1288 04, 12B1288 01, 12
Video Bright SignalB1289 02, 13B1289 04, 13B1289 01, 13
Ground Terminal 81
Ground Terminal 141
1. One or both seatback displays inoperative 2. Both seatback displays inoperative 3. All infotainment devices controlled by circuit inoperative, no sound from speakers 4. One or more infotainment devices controlled by circuit inoperative 5. Power state of all infotainment devices controlled by circuit cannot be controlled by radio 6. No or distorted audio heard in wireless headphones 7. No or distorted left channel audio heard in wireless headphones 8. No or distorted right channel audio heard in wireless headphones 9. No or distorted image in seatback display 10. Serious damage to radio can occur 11. Infrared remote control inoperative 12. Seatback display mode cannot be controlled/changed 13. Seatback display brightness cannot be controlled/adjusted

The radio can command the seatback video display mode on vehicles equipped with rear seat entertainment (RSE) video. The radio utilizes discreet mode control circuits to each display to control the screen display mode via a pulse width modulated signal. If the display screen does not receive a signal, the display screen will operate in a default full screen mode.

  1. Ignition ON.
  2. Battery voltage must be between 9-16 volts.

The radio detects a short to voltage, short to ground, or an open/high resistance in the video display mode control circuit 400 ms after the radio activates the remote enable circuit.

The radio sets the DTC and defaults the video display to normal mode.

  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»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, radio ON, DVD playing.
  2. Verify the display mode of the seatback video displays can be controlled using the infrared remote control to change the display mode. If the display mode cannot be controlled. Refer to Circuit/System Testing below. If the display mode can be controlled.
  3. All OK.
  1. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down
  2. Disconnect the harness connector at the appropriate P22 seatback video display.
  3. Ignition ON, radio ON, DVD playing.
  4. Test for 190-210 HZ DC between the control circuit terminal 15 and ground. If not between 190-210 HZ DC. Ignition OFF, disconnect the X2 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If between 190-210 HZ DC.
  5. Test or replace the P22 driver seatback video display.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Video Display Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Video Display B+21
Remote Enable Control CircuitB1265 02, 345
DVD Audio Common Signal (-)666
Left DVD Audio Signal (+)777
Right DVD Audio Signal (+)888
DVD Video Signal (+)997
DVD Video Signal (-)999, 10
Infrared Remote Signal (+)111111
Infrared Remote Signal (-)111111
Video Mode SignalB1288 02, 12B1288 04, 12B1288 01, 12
Video Bright SignalB1289 02, 13B1289 04, 13B1289 01, 13
Ground Terminal 81
Ground Terminal 141
1. One or both seatback displays inoperative 2. Both seatback displays inoperative 3. All infotainment devices controlled by circuit inoperative, no sound from speakers 4. One or more infotainment devices controlled by circuit inoperative 5. Power state of all infotainment devices controlled by circuit cannot be controlled by radio 6. No or distorted audio heard in wireless headphones 7. No or distorted left channel audio heard in wireless headphones 8. No or distorted right channel audio heard in wireless headphones 9. No or distorted image in seatback display 10. Serious damage to radio can occur 11. Infrared remote control inoperative 12. Seatback display mode cannot be controlled/changed 13. Seatback display brightness cannot be controlled/adjusted

The radio can control the seatback video display brightness on vehicles equipped with rear seat entertainment (RSE) video. A single brightness control circuit is used by the radio to control the display screen brightness for both displays via a pulse width modulated signal. If the display screen does not receive a signal, the display screen will operate at default brightness, which is a middle brightness level.

  1. Ignition ON.
  2. Battery voltage must be between 9-16 volts.

The radio detects a short to voltage, short to ground, or an open/high resistance in the video display brightness control circuit 400 ms after the radio activates the remote enable circuit.

The radio sets the DTC and defaults the video display to full brightness.

  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»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, radio ON, DVD playing.
  2. Verify the display brightness of the seatback video displays can be controlled using the infrared remote control to change the display mode. If the display brightness cannot be controlled. Refer to Circuit/System Testing below. If the display brightnes can be controlled.
  3. All OK.
  1. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down
  2. Disconnect the harness connectors at both of the P22 seatback video displays.
  3. Test for 190-210 HZ DC between the control circuit terminal 16 and ground at each display. If not between 190-210 HZ DC. Ignition OFF, disconnect the X2 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If between 190-210 HZ DC.
  4. Ignition OFF. Connect the harness connector at the P22E driver seatback video display.
  5. Ignition ON, radio ON, DVD playing.
  6. Test for 190-210 HZ DC between the video brightness control circuit terminal 16 and ground at the P22F passenger seatback video display. If not between 190-210 HZ DC. Test or replace the P22E driver seatback video display If between 190-210 HZ DC.
  7. Test or replace the P22F passenger seatback video display.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Video Display Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Backup Battery B+B1447 04
Backup Battery Low ReferenceB1447 04

The backup power source provides voltage to the Telematics Communication Interface Control Module, to be able to successfully place a call in the event of a main battery disconnect during a collision event.

B1446 03

  1. Ignition is ON or in Service Mode.
  2. System voltage is between 9.5 and 15.5 V.
  3. DTC B1447 is not set.

B1447 04

  1. Ignition is ON or in Service Mode.
  2. System voltage is between 9.5 and 15.5 V.
  3. The above conditions are present for greater than 10 seconds.

B1446 03

The Telematics Communication Interface Control Module detects that the backup power source voltage has dropped below the minimum threshold value.

B1447 04

The Telematics Communication Interface Control Module detects no voltage from the backup power source.

B1446 03

The OnStar® status LED turns red.

B1447 04

  1. The OnStar® status LED turns red.
  2. The Telematics Communication Interface Control Module will be unable to place a call in the event of a main battery disconnect during a collision event.
  1. A current DTC B1446 will clear when the Telematics Communication Interface Control Module detects the voltage of the backup power source is above the minimum threshold value.
  2. A current DTC B1447 will clear when the Telematics Communication Interface Control Module detects voltage from the backup power source.
  3. A history DTC clears after 50 malfunction-free ignition cycles.
  1. Shorting the backup power source positive voltage circuit to the backup power source ground circuit or chassis ground will activate the internal circuit protection of the backup power source, rendering the backup power source inoperable.
  2. DTC B1447 may set if the K73 Telematics Communication Interface Control Module has been incorrectly disconnected or serviced. When disconnecting the K73 Telematics Communication Interface Control Module, disconnect the harness connector X1 at the K73 Telematics Communication Interface Control Module prior to disconnecting any other harness connectors. This will ensure the backup power source is preserved when voltage is removed from the K73 Telematics Communication Interface Control Module.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  2. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  3. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
  4. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the C3 Telematics Communication Interface Control Module battery. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for greater than 9.5 V between the B+ circuit terminal A and low reference circuit terminal B. If 9.5 V or less Replace the C3 Telematics Communication Interface Control Module battery. If greater than 9.5 V
  3. Replace the K73 Telematics Communication Interface Control Module.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Communication Interface Module Battery Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Telematics Communication Interface Control Module replacement, programming and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Microphone High Signal CircuitB2455 02B2455 041
Microphone Low Signal Circuit1B2455 04B2455 04
1. OnStar Microphone Inoperative - Caller Cannot Be Heard

The Telematics Communication Interface Control Module provides the Cellular Phone Microphone with a supplied voltage on the Cellular Phone microphone high signal circuit. When the microphone is in use, voice data from the user is sent back to the Telematics Communication Interface Control Module on the microphone low signal circuit.

  1. The ignition must be in the RUN or ACC position.
  2. The system voltage is at least 9.5 V and no more than 15.5 V.
  3. All the above conditions are present for greater than 10 seconds.

B2455 02

The Telematics Communication Interface Control Module detects an short to ground in the Cellular Phone microphone high signal circuit for 10 seconds or greater.

B2455 04

The following conditions will set this DTC

  1. The Telematics Communication Interface Control Module detects an open/high resistance in the Cellular Phone microphone high signal circuit for 10 seconds or greater.
  2. The Telematics Communication Interface Control Module detects an open/high resistance in the microphone low signal circuit for 10 seconds or greater.
  1. The OnStar® status LED turns red.
  2. The Telematics Communication Interface Control Module will not receive a signal from the Cellular Phone Microphone.
  3. Calls can be placed but the caller cannot be heard.
  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 50 consecutive malfunction-free ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. It is necessary to have the vehicle in a quiet, open outside area where a cellular call can be successfully placed and GPS data can be received from satellites.

  1. Ignition ON.
  2. Verify that DTC B2455 is set. If DTC B2455 is not set Refer to «OnStar Microphone Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If DTC B2455 is set
  3. Verify that your voice is heard clearly by the OnStar Call Center after completing a blue button press. If your voice can not be heard clearly Refer to Circuit/System Testing below. If your voice can be heard clearly
  4. All OK.
  1. Ignition OFF, disconnect the harness connector at the B24 Cellular Phone Microphone, ignition ON.
  2. Test for 9.5-10.5 V between the microphone high signal circuit terminal B and ground. If less than 9.5 V Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground in the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the vehicle K73 Telematics Communication Interface Control Module. If greater than 10.5 V Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K73 Telematics Communication Interface Control Module. If between 9.5-10.5 V
  3. Ignition ON.
  4. Test for less than 1 V between the microphone low singal circuit terminal A and ground. If greater than 1 V Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage in the circuit. If less than 1 V, repair the K73 Telematics Communication Interface Control Module. If less than 1 V
  5. Test for 9.5-10.5 V between the microphone high signal circuit terminal B and the microphone high signal circuit terminal A. If not between 9.5-10.5 V Ignition OFF, disconnect the connector X2 at the K73 Telematics Communication Interface Control Module. Test for infinite resistance between the microphone low signal circuit and ground. If less than infinite resistance, repair the short to ground in the circuit. If infinite resistance Test for less than 2 ohms in the microphone low signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K73 Telematics Communication Interface Control Module. If between 9.5-10.5 V
  6. Test or replace the B24 Cellular Phone Microphone.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Mobile Telephone Microphone Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Telematics Communication Interface Control Module replacement, programming and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The navigation antenna is connected to the telematics communication interface control module and the radio through the navigation signal splitter. The navigation signal splitter distributes the navigation signal to both the telematics communication interface control module and the navigation radio. The telematics communication interface control module supplies 5 V through the coax cable to power the internal antenna amplifier through the signal splitter. The radio supplies 5 V through the center conductor of the coax cable to power the splitter.

  1. Radio On.
  2. System voltage is greater than 9 V and less than 16 V.
  3. The navigation radio tests the GPS antenna every 10 seconds.

B2462 01

The navigation radio detects a short to B+ on the GPS antenna signal circuit.

B2462 02

The navigation radio detects a short to ground on the GPS antenna signal circuit.

B2462 04

The navigation radio detects an open/high resistance on the GPS antenna signal circuit.

  1. The radio uses the last reported position and the vehicle speed signal to calculate the vehicle position.
  2. Route guidance may be inaccurate.
  3. Turn by turn navigation may be inaccurate or inoperative.
  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 50 consecutive malfunction-free ignition cycles have occurred.
  1. This DTC can only be retrieved from the radio. The telematics communication interface control module does not set this DTC.
  2. The radio only monitors the connection between the navigation signal splitter and the radio. The radio cannot detect faults between the signal splitter and the navigation antenna. Faults between the signal splitter and the navigation antenna will result in a loss of GPS signal without setting DTC B2462.
  3. The navigation antenna requires a clear line of sight to the sky to operate properly. The GPS may have limited, intermittent, or no reception near tall buildings or inside structures.

Schematic Reference

  1. «OnStar Schematics»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Radio/Navigation System Schematics»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)

Connector End View Reference

Description and Operation

  1. «OnStar Description and Operation»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__onstar-description-and-operation)
  2. «Radio/Audio System Description and Operation»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__radioaudio-system-description-and-operation)

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-49903 OnStar Antenna Diagnostic Tool Kit

  1. Ignition OFF, disconnect the navigation antenna coax cable connector at the A11 radio. Connect the EL-49903 GM OnStar antenna diagnostic tool kit to the A11 radio, place the test antenna on the roof of the vehicle.
  2. Ignition ON, radio ON, navigation selected.
  3. Verify DTC B2462 is not set. If DTC B2462 is set Replace the A11 radio. If DTC B2462 is not set
  4. Ignition OFF, disconnect the radio navigation coax cable at the T15 navigation signal splitter.
  5. Verify the radio navigation coax cable passes the coax cable component test. Refer to Component Testing below. If the coax cable does not pass the test Replace the coax cable If the coax cable passes the test
  6. Test or replace the T15 navigation signal splitter.
CAUTIONRefer to Test Probe Caution .

Note. Before testing the coax cable, check the cable exterior for being pinched, cut, damaged, or having loose connections at the components, which can cause reception issues. To prevent false reading when testing the center coax terminals, use care not to ground the test probe on the outer housing/shield.

Coax Cable Test

  1. Ignition OFF, disconnect the coax cable at both components.
  2. Test for less than 5 ohms between coax cable center terminal end to end. If 5 ohms or greater Replace the coax cable If less than 5 ohms
  3. Test for less than 5 ohms between the coax cable outer shield end to end. If 5 ohms or greater Replace the coax cable If less than 5 ohms
  4. Test for infinite resistance between the coax cable center terminal and the coax cable outer shield. If less than infinite resistance Replace the coax cable If infinite resistance
  5. All OK

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Navigation Signal Splitter Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Cellular Antenna SignalB2470 02B2470 04

The cellular phone and navigation antenna is connected to the Telematics Communication Interface Control Module. This module supplies 5 V to the cellular phone and navigation antenna to power the internal amplifier. When the vehicle is equipped with the optional navigation radio, a T15 Navigation Antenna Signal Splitter is installed to distribute the GPS signal to both the Telematics Communication Interface Control Module and the navigation radio. The navigation radio supplies 5 V through the GPS antenna coaxial cable to the T15 Navigation Antenna Signal Splitter to power the internal navigation radio signal amplifier.

  1. Ignition in the RUN or ACC position.
  2. System voltage is between 9.5 V and 15.5 V.
  3. The above conditions are present for greater than 1 second.

The Telematics Communication Interface Control Module does not detect the presence of a cellular phone antenna.

  1. The vehicle is unable to connect to the OnStar® Call Center.
  2. The OnStar® status LED turns red.
  1. The Telematics Communication Interface Control Module detects the presence of a cellular phone antenna.
  2. A history DTC clears after 50 malfunction-free ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-49903 GM OnStar Antenna Diagnostic Tool Kit

Note. The following verification requires the vehicle to be outside with an unobstructed view of the southern sky. Allow 5 minutes after turning the ignition ON for the GPS satellites to acquire vehicle signal.

  1. Ignition ON.
  2. Verify that DTC B2470 is not set. If DTC B2470 is set Refer to Circuit/System Testing below. If DTC B2470 is not set
  3. Verify that a call can be successfully placed to the OnStar Call Center by pressing the blue OnStar button. If unable to connect with the OnStar Call Center. Refer to «Unable to Contact OnStar Call Center»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) If able to connect with the OnStar Call Center
  4. All OK.

Note. The vehicle may be equipped with sectioned coax. Test each section and replace only the faulty section, not the entire length of coax. The following verification requires the vehicle to be outside with an unobstructed view of the southern sky. Allow 5 minutes after turning the ignition ON for the GPS satellites to acquire vehicle signal.

Without Navigation Radio

  1. Ignition OFF and all vehicle systems OFF, disconnect the GPS and cellular coax cable connector at the K73 Telematics Communication Interface Control Module. It may take up to 2 minutes for all vehicle systems to power down.
  2. Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable), connect the EL-49903 GM OnStar antenna diagnostic tool kit to the K73 Telematics Communication Interface Control Module. Place the test antenna on the roof of the vehicle, ignition ON.
  3. Verify the DTC does not set while operating the vehicle within the conditions for running the DTC. If the DTC sets Replace the K73 Telematics Communications Interface Control Module. If the DTC does not set
  4. Ignition OFF.
  5. Disconnect the EL-49903 GM OnStar antenna diagnostic tool kit from the K73 Telematics Communication Interface Control Module
  6. Test the coax cable. Refer to Component Testing below. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test
  7. Test or replace the T4G Cellular Phone, Navigation, and Digital Radio Antenna.

With Navigation Radio

  1. Ignition OFF and all vehicle systems OFF, disconnect the GPS and cellular coax cable connector at the K73 Telematics Communication Interface Control Module. It may take up to 2 minutes for all vehicle systems to power down.
  2. Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable), connect the EL-49903 GM OnStar antenna diagnostic tool kit to the K73 Telematics Communication Interface Control Module. Place the test antenna on the roof of the vehicle, ignition ON.
  3. Verify the DTC does not set while operating the vehicle within the conditions for running the DTC. If the DTC sets Replace the K73 Telematics Communication Interface Control Module. If the DTC does not set
  4. Ignition OFF, connect the coax cable to the K73 Telematics Communications Interface Control Module and disconnect the coax cable from the T15 Navigation Antenna Signal Splitter, ignition ON.
  5. Test for 4.5-5.5 V between the coax cable center conductor and the outer shield. If greater than 5.5 V Test or replace the coax cable. If less than 4.5 V Test or replace the coax cable. If between 4.5-5.5 V
  6. Ignition OFF.
  7. Test the coax cable between the T15 Navigation Antenna Signal Splitter and the T4G Cellular Phone, Navigation, and Digital Radio Antenna. Refer to Component Testing. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test
  8. Test or replace the T15 Navigation Antenna Signal Splitter.
CAUTIONRefer to Test Probe Caution

Note. Before testing the coax cable, check the cable exterior for being pinched, cut, damaged, or having loose connections at the components, which can cause reception issues. To prevent false readings when testing the center coax terminals, use care not to ground the test probe on the outer housing/shield.

Coax Cable Test

  1. Ignition OFF, disconnect the coax cable at both components.
  2. Test for less than 5 ohms between the coax cable center terminal end to end. If 5 ohms or greater Replace the coax cable. If less than 5 ohms
  3. Test for greater than 5 ohms between the coax cable outer shield end to end. If 5 ohms or greater Replace the coax cable. If less than 5 ohms
  4. Test for infinite resistance between the coax cable center terminal and the coax cable outer shield. If less than infinite resistance Replace the coax cable. If infinite resistance
  5. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Navigation Signal Splitter Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Radio Antenna Base Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  3. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Telematics Communication Interface Control Module replacement, programming and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
10 V ReferenceB2476 04
Signal Terminal 311B2476 59, B2482 00
GroundB2476 04
1. OnStar® Buttons Inoperative

The OnStar® button assembly consists of 3 buttons: Call/Answer, OnStar® Call Center, and OnStar® Emergency. The telematics communication interface control module supplies the OnStar® button assembly with 10 V via the 10 V reference circuit. Each of the buttons, when pressed, completes the circuit across a resistor allowing a specific voltage to be returned to the telematics communication interface control module over the keypad signal circuit. Depending upon the voltage range returned, the telematics communication interface control module is able to identify which button has been pressed.

  1. Ignition ON.
  2. Battery voltage must be between 9-16 V.

B2476 04

The telematics communication interface control module detects an open/high resistance on the keypad supply voltage circuit.

B2482 and B2476 59

The telematics communication interface control module detects a valid signal on the keypad signal circuit for longer than 15 seconds. If one of the OnStar® buttons is held or stuck for 15 seconds or greater, the telematics communication interface control module will set this DTC.

  1. The OnStar® status LED turns red.
  2. No calls can be placed.
  3. The telematics communication interface control module will ignore all inputs from the OnStar® button assembly.
  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clear once 50 consecutive malfunction-free ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. Contact the OnStar® Call Center first before pressing the emergency button in order to notify them of the test.

  1. Ignition ON.
  2. Verify that each button of the S51 telematics button assembly operates normally by pressing each button individually. If none of the buttons operate normally Refer to Circuit/System testing below. If some, but not all, of the buttons operate normally Test or replace the A10 inside rearview mirror If all of the buttons operate normally
  3. All OK.
  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the A10 inside rearview mirror. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 15 ohms between the ground circuit terminal 5 and ground. If 15 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 15 ohms
  3. Ignition ON.
  4. Test for 9.5-10.5 V between the 10 V reference circuit terminal 4 and ground. If less than 9.5 V Ignition OFF, disconnect the harness connector at the K73 telematics communication interface control module. Test for infinite resistance between the 10 V reference circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the 10 V reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K73 telematics communication interface control module. If greater than 10.5 V Ignition OFF, disconnect the harness connector at the K73 telematics communication interface control module, ignition ON. Test for less than 1 V between the 10 V reference circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K73 telematics communication interface control module. If between 9.5-10.5 V
  5. Ignition OFF.
  6. Test for 500-900 ohms between the signal circuit terminal 3 and ground. If less than 500 ohms Disconnect the X1 harness connector at the K73 telematics communication interface control module. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K73 telematics communication interface control module. If greater than 900 ohms Disconnect the X1 harness connector at the K73 telematics communication interface control module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K73 telematics communication interface control module. If between 500-900 ohms
  7. Test or replace the A10 inside rearview mirror.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Inside Rearview Mirror Replacement»(/buick/lacrosse/ii-2009-2013/remont/mirrors/#mirror-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for telematics communication interface control module replacement, programming and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
SignalB2485 02B2485 04

The Bluetooth ® antenna is a small fixed antenna connected directly to the telematics communication interface control module and is used to send and receive signals from a Bluetooth ® enabled cellular phone. The antenna utilizes no cabling and is not external to the vehicle.

  1. The ignition is in OFF, ACCESSORY or RUN position.
  2. The system voltage is between 9-16 V.
  3. The telematics communication interface control module tests the antenna once every second.

B2485 02

  1. The signal voltage is less than 1 V.
  2. The above conditions must be met for 500 ms.

B2485 04

  1. The signal voltage is greater than 2 V.
  2. The above conditions must be met for 500 ms.

Actions Taken When the DTC Sets

  1. The OnStar ® status LED turns red.
  2. Bluetooth ® functionality is disabled.
  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»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
  1. Ignition ON.
  2. Verify that DTC B2458 is not set. If DTC B2485 is set Refer to Circuit/System testing below. If DTC B2485 is not set
  3. All OK.
  1. Verify that the T4S wireless communication antenna - Bluetooth ® is properly connected to the K73 telematics communication interface control module and is not damaged. If the antenna is disconnected Connect the T4S wireless communication antenna - Bluetooth ® to the module. If the antenna is damaged Test or replace the T4S wireless communication antenna - Bluetooth ®. If the antenna is connected and not damaged
  2. Ignition ON.
  3. Verify DTC B2485 is not set. If the DTC is set Test or replace the T4S wireless communication antenna - Bluetooth ®. Clear the DTC, ignition OFF. Ignition ON. Verify the DTC is not set. If the DTC is set, replace the K73 telematics communication interface control module. If the DTC is not set All OK. If the DTC is not set
  4. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Wireless Communication Interface Antenna Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for telematics communication interface control module replacement, programming and setup.

Symptoms - Cellular Communication

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

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) before using the Symptom Tables in order to verify that all of the following are true: There are no DTCs 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 «OnStar Description and Operation»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__onstar-description-and-operation) .

Visual/Physical Inspection

  1. Inspect for aftermarket devices which could affect the operation of the Radio/Audio System. Refer to «Checking Aftermarket Accessories»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__checking-aftermarket-accessories) .
  2. Inspect for 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 .

Symptom List

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

  1. «Bluetooth Malfunction (OnStar)»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) , «Bluetooth Malfunction (Radio)»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «No Global Positioning System (GPS) Reception»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  3. «OnStar Microphone Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  4. «OnStar Audio Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  5. «OnStar Button LED Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  6. «OnStar Call Center Remote Function Requests Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  7. «OnStar Button Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  8. «Unable to Contact OnStar Call Center»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  9. «OnStar Voice Recognition Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  10. «OnStar Steering Wheel Control Functions Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__onstar-steering-wheel-control-functions-malfunction)

Symptoms - Entertainment

IMPORTANTThe following steps must be completed before using the symptom table.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) before using the Symptom Tables in order to verify that all of the following are true: There are no DTCs 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 «Radio/Audio System Description and Operation»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__radioaudio-system-description-and-operation) .
  1. Inspect for aftermarket devices which could affect the operation of the Radio/Audio System. Refer to «Checking Aftermarket Accessories»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__checking-aftermarket-accessories) .
  2. Inspect for easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

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

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

  1. «Application Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Audio/Video Player Adapter - Audio or Video Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  3. «Auxiliary Audio Input Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  4. «Bluetooth Malfunction (OnStar)»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) , «Bluetooth Malfunction (Radio)»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  5. «Digital Radio Poor or No Reception»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  6. «Navigation System - Voice Recognition Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  7. «No Global Positioning System (GPS) Reception»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  8. «Radio Controls Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  9. «Radio Information Display Malfunction - DTC U0257»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  10. «Radio Poor Reception»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  11. «Speaker Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  12. «Video Entertainment System Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  13. «Video Entertainment System Remote Control Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  14. «Video Entertainment System Wireless Headphone Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

The term application refers to any piece of software that works on a system (hardware) that is being operated by it's own software. Applications are typically small software programs which uses the hardware to perform a specific task, as opposed to operating the entire system.

  1. For an application to be used, it must be installed on both the vehicle infotainment system and a compatible mobile device.
  2. The application must work correctly on the device to work with the vehicle infotainment system.
  3. The user may be required to log-in to the application on the mobile device before using the application from the vehicle controls.
  4. Applications use the mobile device and connection to a service provider to operate. Connection quality issues, or service provider data transmission issues can give the appearance of a vehicle malfunction.
  5. The device must be connected to the system. This may be done wirelessly via Bluetooth ®, or via the vehicle USB port. When a mobile device is connected via Bluetooth®, some or all of the device controls may be unavailable from the radio controls. This varies dependant upon the device being used. Refer to the vehicle owners manual, supplements, and the device manufacturers information for information on devices, control, and operation. Refer to the device manufacturers information for the preferred connection method.
  6. The device must be unlocked, and any additional applications should be closed.
  7. If the device has any sound enhancement features such as noise reduction or echo control, these features should be turned off.
  8. A low battery condition in the mobile device may not allow the device to connect to the system, or can create communication issues with the device. Verify the device battery state of charge and re-charge or replace as needed.
  9. If a 'Please See Device' or similar type error message is displayed, this may indicate the device has lost it's connection to the vehicle, or the device has lost it's external data connection.
  10. If a cable is used for connection, attempt to connect the device using a different cable; cables can deteriorate over time or become damaged.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Verify the application is installed on the mobile device and is up to date. If the application is not installed or is not up to date. Install or update the application on the device. If the application is installed on the mobile device and is up to date
  2. Verify the application operates correctly on the mobile device. If the application is not operating correctly on the mobile device. Refer to the application website. If the application is operating correctly on the mobile device.
  3. Verify the radio calibrations are current. If the radio calibrations are not current Reprogram the radio and re-evaluate the concern. If no update calibrations are available
  4. Verify the application is installed on the radio and is up to date. If the application is not installed or is not up to date. Install or update the application on the radio. If the application is installed on the radio and is up to date
  5. Ignition ON, radio ON.
  6. Verify the mobile device can connect to the infotainment system. Refer to the owners manual for information on the preferred connection method for the device. If the mobile device cannot connect to the vehicle infotainment system. If unable to connect via Bluetooth, refer to «Bluetooth Malfunction (OnStar)»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) , «Bluetooth Malfunction (Radio)»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If unable to connect via USB, refer to «Auxiliary Audio Input Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If the mobile device connects to the vehicle infotainment system.
  7. Launch the application.
  8. Verify the applications operates properly with the vehicle infotainment system. If the application does not function properly Refer to diagnostic aids above. If the application functions properly
  9. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio replacement, programming, and setup.

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Right Auxiliary Audio Signal111
Left Auxiliary Audio Signal222
Auxiliary Audio Common Ground1, 2
Auxiliary Video Ground3
Auxiliary Video High Signal333
1. No or distorted right side audio 2. No or distorted left side audio 3. No or distorted video

The audio/video adaptor allows the connection of audio and video signals from an external device to the rear seat entertainment system. The left jack is for video (yellow), the middle jack is for left audio (white), and the right jack is for right audio (red) The system requires standard RCA cables to connect the external device to the RCA jacks. The auxiliary audio and video circuits are connected to the radio.

Verify the external audio or video device is operating normally before performing this diagnostic procedure.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

IMPORTANTVerify the DVD player in the radio is operating normally before performing this diagnostic procedure. If there is any issues with operating the DVD player, refer to Symptoms - Entertainment .
  1. Ignition OFF, disconnect the harness connector at the X82 audio/video input adapter and the X2 harness connector at the A11 radio. Ignition ON.
  2. Test for less then 1 V between the signal circuit terminals listed below and ground: A11 radio terminal 3 X2 A11 radio terminal 13 X2 A11 radio terminal 14 X2 A11 radio terminal 7 X2 A11 radio terminal 17 X2 If 1 V or greater. Repair the short to voltage on the circuit. If less than 1 V.
  3. Ignition OFF.
  4. Test for infinite resistance between the signal circuit terminals listed below and ground: A11 radio terminal 3 X2 A11 radio terminal 13 X2 A11 radio terminal 14 X2 A11 radio terminal 7 X2 A11 radio terminal 17 X2 If less than infinite resistance. Repair the short to ground on the circuit. If infinite resistance.
  5. Test for less then 2 ohms between signal circuit terminals listed below and ground: A11 radio terminal 3 X2 and the X82 audio/video input adapter terminal 6 A11 radio terminal 13 X2 and the X82 audio/video input adapter terminal 5 A11 radio terminal 14 X2 and the X82 audio/video input adapter terminal 7 A11 radio terminal 7 X2 and the X82 audio/video input adapter terminal 3 A11 radio terminal 17 X2 and the X82 audio/video input adapter terminal 1 If 2 ohms or greater. Repair the open/high resistance in the circuit. If less then 2 ohms.
  6. Replace the X82 audio/video input adapter.
  7. Connect all harness connectors. Ignition ON, radio ON.
  8. Verify the entertainment system displays video playing from a device connected to the X82 audio/video input adapter. If the entertainment system does not display video playing from a device. Test or replace the A11 radio. If the entertainment system displays video playing from a device.
  9. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Audio/Video Disc Player Adapter Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Multimedia Player B+4
Detection Signal Circuit455
Left Audio Signal Multimedia Player Terminal 12B1278 02, 33B1278 01, 3
Left Audio Signal Radio Terminal 24333
Right Audio Signal Multimedia Player Terminal 13B1279 02, 22B1279 01, 2
Right Audio Signal Radio Terminal 10222
Audio Common Circuit Multimedia Player Terminal 31, 5
Audio Common Circuit Radio Terminal 231
USB Cable666
Multimedia Player Ground4
1. No or distorted audio from both sides 2. No or distorted right side audio 3. No or distorted left side audio 4. External audio inputs inoperative 5. AUX selection always available with or without device connected 6. USB port Inoperative

Auxiliary Audio Input Jack

The 3.5 mm (1/8 in.) auxiliary audio input jack is located in the console. The auxiliary input jack circuits may be connected directly to the radio, or to the multimedia player interface module (if equipped). When a portable audio playback device is connected to the auxiliary jack, an internal switch opens the detection signal circuit and the radio will switch to AUX as the audio source.

When not equipped with the multimedia player interface module, all circuits from the auxiliary jack are connected directly to the radio. When a device is connected to the auxiliary jack an internal switch opens. The radio detects the device and switches to AUX as the audio source. Audio signals from the device are sent to the radio from the auxiliary input jack via the left, right, and common audio signal circuits.

When equipped with the multimedia player interface module, all circuits from the auxiliary jack are connected directly to the multimedia player interface module. When a device is connected to the auxiliary jack an internal switch opens. The multimedia player interface module detects the device and sends a serial data request to radio to switch to AUX as the audio source. Audio signals from the device are sent to the multimedia player interface module from the auxiliary input jack via the left, right, and common audio signal circuits. The multimedia player interface module then outputs these signals to the radio.

USB Port

The vehicle may be equipped with a USB port in the console. This port allows USB connectivity to the infotainment system from portable media players or a USB storage device (memory stick/flash drive). When a device is connected to the USB port, the system detects the device and switches to USB as the audio source. Once connected, the device can be controlled from the radio controls.

The USB port is connected to the radio or multimedia player interface module (if equipped) via a standard USB cable. Mini type USB connectors are used to connect the cable at the USB port and at the radio or multimedia player interface module. Standard USB male to female connections are typically used for connecting USB cables together where an in-line connection is required. An in-line cable connection is typically found between the console and I/P harness.

Not all portable media player devices are compatible. Memory stick/flash drive capability is limited to MP3 and WMA file types only. Video transfer from any device is not supported. Refer to the owner's manual for information on USB devices, control, and operation.

Multimedia Player Interface Module (if equipped)

The multimedia player interface module is a device that is capable of receiving inputs from analog or digital audio playback devices. When equipped with RPO KTA, inputs can be received via the auxiliary input jack or USB. With RPO KTB, the multimedia player interface module has the additional capability of receiving inputs via Bluetooth®. The multimedia player interface module and the radio communicate via serial data. Messages are used for the radio to control the input source, and for the multimedia player interface module to send detection information to the radio when devices are connected. The multimedia player interface module is used to provide capability for these inputs in systems where the radio does not provide native support.

The multimedia player interface module receives the inputs from the device, and transfers the audio signals to the radio for playback. All multimedia player interface module inputs are transferred to the radio as analog audio signals via left, right, and common audio circuits.

Auxiliary Audio Input Jack

  1. When a device is first connected to the 3.5 mm (1/8 in.) input jack the infotainment system automatically switches to that device. If an auxiliary device has already been connected, press the AUX or CD/AUX button to select the device.
  2. If the system detects the device, but the audio is not heard or is not clear, attempt to connect the device using a different cable; cables can deteriorate over time or become damaged.
  3. Playback of an audio device that is connected to the 3.5 mm jack can only be controlled using the controls on the device.
  4. The volume control on the device may need to be adjusted to ensure sufficient playback volume through the infotainment system.

USB

  1. When a device is first connected to the USB port, the infotainment system automatically switches to that device. If an auxiliary device has already been connected, press the AUX or CD/AUX button to select the device.
  2. A low battery condition in a portable media player may not allow the device to connect to the system, or can create communication issues with the device. Verify the device battery state of charge and re-charge or replace as needed.
  3. Connect the device directly to the USB port if possible. Only use a cable if it is required to connect the device. The use of extension cables can cause communication issues.
  4. If a cable is required for connection, attempt to connect the device using a different cable; cables can deteriorate over time or become damaged.
  5. Attempt audio playback from multiple USB devices when diagnosing USB concerns. Device compatibility can vary based on vehicle equipment. If the infotainment system is capable of operating any USB type device, the cause of the concern is not with the vehicle system. The inoperative device(s) may be incompatible or contain no recognized media types.
  6. If a 'Device Not Supported' or similar type error message is displayed, this indicates the system has connected to the device but cannot communicate with it properly. This does not indicate an issue with the vehicle system. The device may be incompatible, may require a 'reset', or may require an update to its software/firmware.
  7. If a 'No Supported Data Found' or similar type error message is displayed, this indicates the system has connected to the device and is communicating, but cannot find any compatible files/data. This does not indicate an issue with the vehicle system. Verify the device contains compatible media/file types.
  8. Poor connections or damaged USB cables can cause intermittent or no operation of USB devices. Inspect connectors, terminals, and cables for damage and replace components as necessary. Ensure all USB inline connections and connections at components are fully seated and connector position retainers/locks are secure.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

  1. EL-50334-20 Multi-Media Interface Tester (MIT)
  2. EL-50334-50 USB Cable and Adapter Kit

Auxiliary Audio Input Jack

  1. Verify no DTCs are present. If any DTCs are present Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . If no DTCs are present
  2. Ignition ON, radio ON.
  3. Verify the infotainment system switches to AUX as the audio source with the EL-50334-20 Multi-Media Interface Tester (MIT) connected to the auxiliary audio input jack. If the infotainment system does not switch to AUX as the audio source Refer to Circuit/System Testing - Auxiliary Input Jack below. If the infotainment system switches to AUX as the audio source
  4. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the vehicle infotainment system while operating the test tool to begin audio playback. If audio is not heard from the test tool Refer to Circuit/System Testing - Auxiliary Input Jack below. If audio is heard from the test tool
  5. All OK

USB Port

  1. Verify no DTCs are present. If any DTCs are present Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . If no DTCs are present
  2. Ignition ON, radio ON.
  3. Verify the infotainment system switches to USB as the audio source with the EL-50334-20 Multi-Media Interface Tester (MIT) connected to the USB port. If the infotainment system does not switch to USB as the audio source Refer to Circuit/System Testing - USB Port below. If the infotainment system switches to USB as the audio source
  4. Verify the audio from the EL-50334-20 Multi-Media Interface Tester (MIT) is heard through the vehicle infotainment system while operating the system to play audio from the test tool. If audio is not heard from the test tool Refer to Circuit/System Testing - USB Port below. If audio is heard from the device
  5. All OK.

Auxiliary Audio Input Jack without Multimedia Player Interface Module

  1. Ignition OFF, disconnect the X1 harness connector at the X83 auxiliary audio input. Ignition ON, radio ON.
  2. Test for 2.5-3.5 V between the signal circuit terminal 5 and ground. If less than 2.5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If greater than 3.5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio, ignition ON. Test for less than 1 V between the detection circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If between 2.5-3.5 V
  3. Test for less than 1 V between the signal circuits listed below and ground: Left auxiliary audio signal circuit terminal 1 Right auxiliary audio signal circuit terminal 2 Auxiliary audio common signal circuit terminal 3 If 1 V greater Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If less than 1 V
  4. Ignition OFF, disconnect the X1 harness connector at the A11 radio.
  5. Test for infinite resistance between the signal circuits listed below and ground: Auxiliary audio common signal circuit terminal 23 Left auxiliary audio signal circuit terminal 24 Right auxiliary audio signal circuit terminal 10 If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
  6. Test for less than 5 ohms between the signal circuit terminals listed below: A11 radio terminal 24 X1 and the X83 auxiliary audio input terminal 1 X1 A11 radio terminal 10 X1 and the X83 auxiliary audio input terminal 2 X1 A11 radio terminal 23 X1 and the X83 auxiliary audio input terminal 3 X1 If 5 ohms greater Repair the open/high resistance in the circuit. If less than 5 ohms
  7. Replace the X83 auxiliary audio input. Connect all harness connectors.
  8. Connect and operate the EL-50334-20 Multi-Media Interface Tester (MIT).
  9. Verify the audio from the test tool is heard through the vehicle infotainment system. If audio is not heard from the test tool Replace the A11 radio. If audio is heard from the test tool
  10. All OK.

USB Port without Multimedia Player Interface Module

  1. Ignition OFF, disconnect the USB cable connection at the A11 radio.
  2. Connect the EL-50334-1 Type A male to Mini A male USB Cable to the A11 radio. Connect the EL-50334-3 Type A female to Type A female adapter to the EL-50334-1 Cable.
  3. Ignition ON, radio ON, connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the EL-50334-3 adapter.
  4. Verify the infotainment system switches to USB as the audio source. If the infotainment system does not switch to USB as the audio source Replace the A11 radio. If the infotainment system switches to USB as the audio source
  5. Ignition OFF, connect the vehicle USB cable to the A11 radio. Disconnect the I/P to floor console inline USB cable connector.
  6. Ignition ON, radio ON, connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the I/P side of the inline USB cable connector.
  7. Verify the infotainment system switches to USB as the audio source. If the infotainment system does not switch to USB as the audio source Replace the I/P USB cable assembly. If the infotainment system switches to USB as the audio source
  8. Ignition OFF, connect the I/P to floor console inline USB cable connector.
  9. Disconnect the USB cable at the X83 auxiliary audio input. Connect the EL-50334-4 Type A female to Mini B female adapter to the USB cable.
  10. Ignition ON, radio ON, connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the EL-50334-4 adapter.
  11. Verify the infotainment system switches to USB as the audio source. If the infotainment system does not switch to USB as the audio source Replace the console USB cable assembly. If the infotainment system switches to USB as the audio source
  12. Test or replace the X83 auxiliary audio input.

Auxiliary Audio Input Jack with Multimedia Player Interface Module

  1. Ignition OFF, disconnect the X1 harness connector at the X83 auxiliary audio input. Ignition ON, radio ON.
  2. Test for 2.5-3.5 V between the signal circuit terminal 5 and ground. If less than 2.5 V Ignition OFF, disconnect the X1 harness connector at the T11 multimedia player interface module. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the T11 multimedia player interface module. If greater than 3.5 V Ignition OFF, disconnect the X1 harness connector at the T11 multimedia player interface module, ignition ON. Test for less than 1 V between the detection circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the T11 multimedia player interface module. If between 2.5-3.5 V
  3. Test for less than 1 V between the signal circuits listed below and ground: Left auxiliary audio signal circuit terminal 1 Right auxiliary audio signal circuit terminal 2 Auxiliary audio common signal circuit terminal 3 If 1 V greater Ignition OFF, disconnect the X1 harness connector at the T11 multimedia player interface module. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the T11 multimedia player interface module. If less than 1 V
  4. Ignition OFF, disconnect the X1 harness connector at the T11 multimedia player interface module.
  5. Test for infinite resistance between the signal circuits listed below and ground: Auxiliary audio common signal circuit terminal 3 Left auxiliary audio signal circuit terminal 12 Right auxiliary audio signal circuit terminal 13 If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
  6. Test for less than 5 ohms between the signal circuit terminals listed below: T11 multimedia player interface module terminal 12 X1 and the X83 auxiliary audio input terminal 1 X1 T11 multimedia player interface module terminal 13 X1 and the X83 auxiliary audio input terminal 2 X1 T11 multimedia player interface module terminal 3 X1 and the X83 auxiliary audio input terminal 3 X1 If 5 ohms greater Repair the open/high resistance in the circuit. If less than 5 ohms
  7. Ignition ON.
  8. Test for less than 1 V between the signal circuits listed below and ground: T11 multimedia player interface module terminal 4 X1 T11 multimedia player interface module terminal 14 X1 T11 multimedia player interface module terminal 15 X1 If 1 V greater Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If less than 1 V
  9. Ignition OFF, disconnect the X1 harness connector at the A11 radio.
  10. Test for infinite resistance between the signal circuits listed below and ground: Auxiliary audio common signal circuit terminal 23 Left auxiliary audio signal circuit terminal 24 Right auxiliary audio signal circuit terminal 10 If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
  11. Test for less than 5 ohms between the signal circuit terminals listed below: A11 radio terminal 10 X1 and the T11 multimedia player interface module terminal 15 X1 A11 radio terminal 23 X1 and the T11 multimedia player interface module terminal 4 X1 A11 radio terminal 24 X1 and the T11 multimedia player interface module terminal 14 X1 If 5 ohms greater Repair the open/high resistance in the circuit. If less than 5 ohms
  12. Replace the X83 auxiliary audio input. Connect all harness connectors.
  13. Connect and operate the EL-50334-20 Multi-Media Interface Tester (MIT).
  14. Verify the audio from the test tool is heard through the vehicle infotainment system. If audio is not heard from the test tool Replace the T11 multimedia player interface module. Connect and operate the EL-50334-20 Multi-Media Interface Tester (MIT). Verify the audio from the test tool is heard through the vehicle infotainment system. If audio is not heard from the test tool Replace the A11 radio. If audio is heard from the test tool All OK. If audio is heard from the test tool
  15. All OK.

USB Port with Multimedia Player Interface Module

  1. Ignition OFF, disconnect the USB cable connection at the T11 multimedia player interface module.
  2. Connect the EL-50334-2 Type A female to Mini B male USB Cable to the T11 multimedia player interface module. Ignition ON, radio ON.
  3. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the EL-50334-2 cable.
  4. Verify the infotainment system switches to USB as the audio source. If the infotainment system does not switch to USB as the audio source Replace the T11 multimedia player interface module. If the infotainment system switches to USB as the audio source
  5. Ignition OFF, connect the vehicle USB cable to the T11 multimedia player interface module. Disconnect the I/P to floor console inline USB cable connector. Ignition ON, radio ON.
  6. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the I/P side of the inline USB cable connector.
  7. Verify the infotainment system switches to USB as the audio source. If the infotainment system does not switch to USB as the audio source Replace the I/P USB cable assembly. If the infotainment system switches to USB as the audio source
  8. Ignition OFF, connect the I/P to floor console inline USB cable connector.
  9. Disconnect the USB cable at the X83 auxiliary audio input. Connect the EL-50334-4 Type A female to Mini B female adapter to the USB cable. Ignition ON, radio ON.
  10. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the EL-50334-4 adapter.
  11. Verify the infotainment system switches to USB as the audio source. If the infotainment system does not switch to USB as the audio source Replace the console USB cable assembly. If the infotainment system switches to USB as the audio source
  12. Ignition OFF, connect the vehicle USB cable to the X83 auxiliary audio input. Ignition ON, radio ON.
  13. Connect the EL-50334-20 Multi-Media Interface Tester (MIT) to the X83 auxiliary audio input.
  14. Verify the infotainment system switches to USB as the audio source. If the infotainment system does not switch to USB as the audio source Replace the X83 auxiliary audio input. If the infotainment system switches to USB as the audio source
  15. Ignition OFF, disconnect the X1 harness connector at the T11 multimedia player interface module. Ignition ON.
  16. Test for less than 1 V between the signal circuits listed below and ground: T11 multimedia player interface module terminal 4 X1 T11 multimedia player interface module terminal 14 X1 T11 multimedia player interface module terminal 15 X1 If 1 V greater Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If less than 1 V
  17. Ignition OFF, disconnect the X1 harness connector at the A11 radio.
  18. Test for infinite resistance between the signal circuits listed below and ground: Auxiliary audio common signal circuit terminal 23 Left auxiliary audio signal circuit terminal 24 Right auxiliary audio signal circuit terminal 10 If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
  19. Test for less than 5 ohms between the signal circuit terminals listed below: A11 radio terminal 10 X1 and the T11 multimedia player interface module terminal 15 X1 A11 radio terminal 23 X1 and the T11 multimedia player interface module terminal 4 X1 A11 radio terminal 24 X1 and the T11 multimedia player interface module terminal 14 X1 If 5 ohms greater Repair the open/high resistance in the circuit. If less than 5 ohms
  20. Replace the T11 multimedia player interface module. Connect all harness connectors. Ignition ON, radio ON.
  21. Connect and operate the EL-50334-20 Multi-Media Interface Tester (MIT).
  22. Verify the audio from the test tool is heard through the vehicle infotainment system. If audio is not heard from the test tool Replace the A11 radio. If audio is heard from the test tool
  23. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio or multimedia player interface module replacement, programming, and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

The Bluetooth ® antenna is a small fixed antenna connected directly to the telematics communication interface control module and is used to send and receive signals from a Bluetooth ® enabled cellular phone. The antenna utilizes no cabling and is not external to the vehicle.

In order to use hands-free calling, the cellular phone must be paired to the vehicle. Up to five devices can be paired to the vehicle at one time, but only one can be connected at any given time. To pair a phone, the customer must know how to operate the Bluetooth ® functionality of their phone. The pairing process must only be done one time for each phone, unless that phone's information is deleted. For safety reasons, the pairing process is disabled while the vehicle is moving.

  1. The purpose of this diagnostic is to verify the ability of the telematics communication interface control module to pair to a Bluetooth ® device.
  2. Before performing this test, verify compatibility of the cellular phone(s) the customer is attempting to use with the vehicle. Based on the cellular phone's service provider and the manufacturer's implementation of Bluetooth ®, not all phones support all available Bluetooth ® functionality. A vehicle and feature compatibility list will be provided via the GM Bluetooth ® website: http://www.onstar.com/web/Bluetooth/
  3. If the vehicle passes the following tests and a compatible device is being used, the concern may be due to a device malfunction or an incomplete/improper pairing attempt.
  4. A Bluetooth ® test tool or equivalent can also be used to verify the ability of the customers cellular phone(s) to pair with another device.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON.
  2. Verify DTC B2485 is not set. If DTC B2485 is set Refer to «DTC B2485»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) If DTC B2485 is not set
  3. Verify that the vehicle appears in the list of available devices when performing the discovery/search operation on a Bluetooth ® test tool or equivalent. If the vehicle does not appear in the list of available devices after repeated attempts Refer to Circuit/System Testing below. If the vehicle appears in the list of available devices
  4. Verify successful pairing with test tool when utilizing instructions provided in the Vehicle Owners Manual. If pairing is not successful after repeated attempts Refer to Circuit/System Testing below. If pairing is successful
  5. All OK.
  1. Ignition ON.
  2. Verify that the vehicle appears in the list of available devices when performing the discovery/search operation on a Bluetooth ® test tool or equivalent. If the vehicle does not appear in the list of available devices after repeated attempts Ignition OFF. Replace the T4S Wireless Communication Antenna - Bluetooth ®. Verify that the vehicle appears in the list of available devices when performing the discover/search operation on a Bluetooth ® test tool or equivalent. If the vehicle does not appear in the list of available devices after repeated attempts, replace the K73 telematics communication interface control module If the vehicle appears in the list of available devices All OK. If the vehicle appears in the list of available devices
  3. Verify successful pairing with test tool when utilizing instructions provided in the Vehicle Owners Manual. If pairing is not successful after repeated attempts Replace the K73 telematics communication interface control module If pairing is successful
  4. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Wireless Communication Interface Antenna Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for telematics communication interface control module replacement, programming and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

Bluetooth ® wireless technology is a short-range communications technology intended to replace the cables connecting portable and/or fixed devices while maintaining high levels of security. The operating range of the signal is approximately 30 feet.

The available features and functions are determined by the type of device and the software within the devices being used. For a feature or function to operate, it must be supported in both devices.

The Bluetooth ® hardware is internal to the radio. The radio supports streaming of data (music, voice, information) from cellular phones and other mobile devices that support those features. The radio may also be capable of interfacing with cellular phones for hands-free features.

Refer to the vehicle owners manual, supplements, and the device manufacturers information for information on devices, control, operation. and pairing instructions.

  1. Verify the mobile device is properly configured for the feature being used. Refer to the device manufacturers information.
  2. Verify the function/feature that is being used is supported by the mobile device.
  3. The device must be paired to the radio to use the available Bluetooth ® feature(s). The pairing process must only be performed once for each device, unless that device's information is deleted.
  4. The system can store pairing information for multiple devices, but can only be actively connected to one at any given time.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-50334-20 Multi-Media Interface Tester (MIT)

  1. Verify no DTCs are present. If any DTCs are present Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . If no DTCs are present
  2. Verify the radio calibrations are current. If the radio calibrations are not current Reprogram the radio and re-evaluate the concern. If no update calibrations are available
  3. Ignition ON, infotainment system ON.
  4. Verify the infotainment system successfully pairs with the MIT tool. If the infotainment system does not successfully pair with the MIT tool. Replace the A11 radio. If the infotainment system successfully pairs with the MIT tool.
  5. Verify the infotainment system successfully completes the desired feature test using the MIT tool. If the feature test is not successful Replace the A11 radio. If the feature test is successful
  6. All OK. Refer to Diagnostic Aids above.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio replacement, programming, and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The digital radio receiver, located inside the radio, receives digital radio information from the digital radio antenna located on the outside of the vehicle. The digital radio receiver is connected to the digital radio antenna via a shielded coax cable.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-48028 Digital Radio Test Antenna

  1. Tune to a strong AM or FM station and verify each speaker is producing clear and even sound, with no distortion. If any speaker is not producing sound or the sound produced is distorted, refer to «Speaker Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) .
  2. With the vehicle outside in an area with an unobstructed view of the southern sky, tune to XM. Verify XM reception is clear and the No XM Signal message is not displayed on the radio.
  1. Ignition OFF, disconnect the digital radio antenna coax from the radio. Connect the EL-48028 digital radio test antenna to the radio and place on the roof of the vehicle. Move the vehicle outside in an area with an unobstructed view of the southern sky.
  2. Ignition ON, radio tuned to XM channel 1, verify XM reception is clear and uninterrupted. If reception is not clear, replace the radio.
  3. Ignition OFF, reconnect the antenna coax cable at the radio. Disconnect the antenna coax cable from the digital radio antenna.
  4. Ignition ON, radio ON, test for 4.5-5.5 V between the antenna coax cable center terminal and outer shield. If less than the specified range, test the antenna coax cable for an open/high resistance. If greater than the specified range, test the antenna coax cable for a short to voltage.
  5. If all circuits test normal, replace the digital radio antenna.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Radio Antenna Base Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Microphone High Signal CircuitB2455 02B2455 041
Microphone Low Signal Circuit1B2455 04B2455 04
1. OnStar Microphone Inoperative - Caller Cannot Be Heard

The Telematics Communication Interface Control Module provides the Cellular Phone Microphone with a supplied voltage on the Cellular Phone Microphone signal circuit. When the Cellular Phone Microphone is in use, voice data from the user is sent back to the Telematics Communication Interface Control Module on the signal circuit.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. It is necessary to have the vehicle in a quiet, open outside area where a cellular call can be successfully placed and GPS data can be received from satellites.

  1. Ignition ON.
  2. Verify that DTC B2455 is not set. If DTC B2455 is set Refer to «DTC B2455»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If DTC B2455 is not set
  3. Verify that your voice is heard clearly by the OnStar Call Center after completing a blue button press. If your voice can not be heard clearly Refer to Circuit/System Testing below. If your voice can be heard clearly
  4. All OK.
  1. Ignition OFF, disconnect the harness connector at the B24 Cellular Phone Microphone, ignition ON.
  2. Test for 9.5-10.5 V between the microphone high signal circuit terminal B and ground. If less than 9.5 V Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground in the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the vehicle K73 Telematics Communication Interface Control Module. If greater than 10.5 V Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K73 Telematics Communication Interface Control Module. If between 9.5-10.5 V
  3. Ignition ON.
  4. Test for less than 1 V between the microphone low singal circuit terminal A and ground. If greater than 1 V Ignition OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage in the circuit. If less than 1 V, repair the K73 Telematics Communication Interface Control Module. If less than 1 V
  5. Test for 9.5-10.5 V between the microphone high signal circuit terminal B and the microphone high signal circuit terminal A. If not between 9.5-10.5 V Ignition OFF, disconnect the connector X2 at the K73 Telematics Communication Interface Control Module. Test for infinite resistance between the microphone low signal circuit and ground. If less than infinite resistance, repair the short to ground in the circuit. If infinite resistance Test for less than 2 ohms in the microphone low signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K73 Telematics Communication Interface Control Module. If between 9.5-10.5 V
  6. Test or replace the B24 Cellular Phone Microphone.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Mobile Telephone Microphone Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Telematics Communication Interface Control Module replacement, programming and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provide an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Voice Recognition Audio Signal111
Voice Recognition Audio Low Reference1
1. navigation voice recognition inoperative

When voice recognition for the navigation equipped infotainment system is started, voice signals from the cellular phone microphone are passed through the telematics communication interface control module to the radio via the voice recognition audio circuits.

  1. Refer to the Navigation System Owners Manual for voice recognition use and commands.
  2. Voice recognition only works if the map database is installed in the system.
  3. Navigation voice commands are not available until the OK button has been selected.
  4. If the radio is off, the only commands available will be Hands Free and Help.
  5. When the system recognizes the command the system will either perform the function or ask to confirm the choice by clearly saying "yes" or "no".
  6. If experiencing difficulty with the system recognizing a command, confirm that the command is correct.
  7. Background noise such as a climate control fan positioned on high, open windows, or very loud outside noises, can cause voice commands to be misunderstood.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Verify the OnStar ® voice recognition system is operating normally. If the OnStar ® voice recognition system is not operating normally. Refer to «OnStar Voice Recognition Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If the OnStar ® voice recognition system is operating normally.
  2. Ignition ON, radio ON.
  3. Begin voice recognition for the radio and clearly speak one of the available commands.
  4. Verify the infotainment system responds correctly to the command. If the infotainment system does not respond correctly to the command. Clearly speak a different command. Verify the infotainment system responds correctly to the command. If the infotainment system does not respond correctly to any commands, refer to Circuit/System Testing below. If the infotainment system responds correctly to the command. Refer to the navigation system owners manual for hints on speaking commands. If the infotainment system responds correctly to the command.
  5. All OK
  1. Ignition OFF, disconnect the X2 harness connector at the K73 telematics communication interface module.
  2. Test for less than 10 ohms between the low reference circuit terminal 12 and ground. If 10 ohms or greater Ignition OFF, disconnect the X3 harness connector at the A11 radio. Test for less than 2 ohms in the low reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If less than 10 ohms
  3. Ignition ON, radio ON.
  4. Test for less than 1 V between the signal circuit terminal 6 and ground. If 1 V greater Ignition OFF, disconnect the X3 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If less than 1 V
  5. Ignition OFF, disconnect the X3 harness connector at the A11 radio.
  6. Test for infinite resistance between the circuits listed below and ground: voice recognition signal circuit A11 radio X3 terminal 6 voice recognition low reference circuit A11 radio X3 terminal 16 If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
  7. Test for less than 5 ohms between the terminals listed below: A11 radio X3 terminal 6 and the K73 telematics communication interface module X2 terminal 6 A11 radio X3 terminal 16 and the K73 telematics communication interface module X2 terminal 12 If 5 ohms greater Repair the open/high resistance in the circuit. If less than 5 ohms
  8. Replace the A11 radio. Connect all harness connectors.
  9. Begin voice recognition for the radio and clearly speak one of the available commands.
  10. Verify the infotainment system responds correctly to the command. If the infotainment system does not respond correctly to the command Clearly speak a different command. Verify the infotainment system responds correctly to the command. If the infotainment system does not respond correctly to any commands, replace the K73 telematics communication interface module. If the infotainment system responds correctly to the command
  11. All OK

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio or telematics communication interface control module replacement, programming, and setup.

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Audio High Signal terminal 1111
Audio Low Signal terminal 2111
1. No (or Noisy) OnStar® Audio

When an OnStar® keypress is made, a serial data message is sent to the audio system to mute all radio functions and output OnStar® originated audio. After the audio system is muted, the Telematics Communication Interface Control Module transmits signals to the audio system on the audio signal and audio common circuits.

Schematic Reference

  1. «OnStar Schematics»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Radio/Navigation System Schematics»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, radio ON.
  2. Verify that audio is heard clearly through all speaker channels when tuning radio to a known good station. If audio is not heard clearly Refer to «Speaker Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) If audio is heard clearly
  3. Verify that the Connecting to OnStar® message is heard clearly through the audio system when the OnStar® blue button is pressed. If OnStar message is noisy or distorted Refer to Circuit/System Testing below. If OnStar message is heard clearly
  4. All OK.
  1. Ignition OFF and vehicle systems OFF, disconnect the X2 harness connector at the K73 Telematics Communication Interface Control Module, ignition ON.
  2. Test for less than 4 V between the signal circuits listed below and ground Audio High Signal Circuit Terminal 1 Audio Low Signal Circuit Terminal 2 If 4 V or greater Ignition OFF, disconnect the X1 harness connector at the A11 Radio, ignition ON. Test for less than 1 V between the signal circuits and ground. If greater than 1 V, repair the short to voltage in the circuit. If less then 1 V, replace the A11 Radio. If less than 4 V
  3. Ignition OFF.
  4. Test for infinite resistance between the signal circuits listed below and ground Audio High Signal Circuit Terminal 1 Audio Low Signal Circuit Terminal 2 If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
  5. Disconnect the X1 harness connector at the A11 Radio.
  6. Test for less than 2 ohms in the signal circuits listed below. Audio High Signal Circuit Terminal 1 Audio Low Signal Circuit Terminal 2 If 2 ohms or greater Repair the open/high resistance in the circuit. If less than 2 ohms
  7. Replace the K73 Telematics Communication Interface Control Module.
  8. Verify that the Connecting to OnStar® message is heard clearly through the audio system when the OnStar® blue button is pressed. If audio is not heard clearly Replace the A11 radio. If audio is heard clearly
  9. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for radio or Telematics Communication Interface Control Module replacement, programming and setup.

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The navigation antenna is connected to the telematics communication interface control module. The module supplies 5 V to the antenna to power the internal amplifier through the center conductor of the antenna coax cable.

When the vehicle is equipped with the optional navigation radio, a navigation signal splitter is installed to distribute the navigation signal to both the telematics communication interface control module and the navigation radio. The telematics communication interface control module supplies 5 V through the coax cable to power the internal antenna amplifier through the signal splitter.

  1. The scan tool telematics communication interface control module GPS signal parameter will display a Yes or No dependent upon whether or not the module sees an increment of the seconds transmitted by GPS signals to the telematics communication interface control module. Upon entering this screen, the GPS signal title will initially display Yes, regardless of the presence of time increment, for at least 2 seconds, while the algorithm in the scan tool determines the status of the clock. If increment is found, Yes is continually displayed. If the clock remains static, No is displayed. The scan tool looks for increment every second, regardless of current display.
  2. Inaccurate or aged GPS position concerns which are no longer present may have been due to the temporary loss of GPS signal reception by the vehicle. Conditions such as tunnels or parking structures will restrict the cellular phone and navigation antenna from a clear view of the satellites in the sky and may have caused this temporary data loss.
  3. The GPS requires a clear line of sight to the sky to operate properly. In most cases the GPS will not have reception near tall buildings or inside structures.

Schematic Reference

  1. «OnStar Schematics»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Radio/Navigation System Schematics»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)

Connector End View Reference

Description and Operation

  1. «OnStar Description and Operation»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__onstar-description-and-operation)
  2. «Radio/Audio System Description and Operation»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__radioaudio-system-description-and-operation)

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-49903 OnStar Antenna Diagnostic Tool Kit

Note. The following verification requires the vehicle to be outside with an unobstructed view of the southern sky. Allow 5 minutes after turning the ignition ON for the GPS satellites to acquire vehicle signal.

  1. Ignition ON.
  2. Verify that no DTCs are set. If any DTCs are set Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . If no DTCs are set
  3. Verify that an OnStar advisor can locate the vehicle after performing a blue button press. If the advisor can not locate the vehicle and the vehicle is not equipped with a navigation radio Refer to Circuit System Testing Without Navigation Radio below. If the advisor can not locate the vehicle and the vehicle is equipped with a navigation radio Refer to Circuit System Testing With Navigation Radio below. If the advisor can locate the vehicle
  4. Verify that the NO GPS symbol/message is not displayed on the radio. If the NO GPS symbol/message is displayed Refer to Circuit System Testing With Navigation Radio below. If the NO GPS symbol/message is not displayed
  5. All OK.

without Navigation Radio

  1. Ignition OFF, disconnect the GPS and cellular coax cable connector at the K73 telematics communication interface control module.
  2. Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable), connect the EL-49903 GM OnStar antenna diagnostic tool kit to the K73 telematics communication interface module. Place the test antenna on the roof of the vehicle, ignition ON.
  3. Verify that an OnStar advisor can locate the vehicle after performing a blue button press. If the advisor can not locate the vehicle Replace the K73 telematics communication interface control module. If the advisor can locate the vehicle
  4. Ignition OFF, disconnect the EL-49903 GM OnStar antenna diagnostic tool kit from the K73 telematics communication interface control module
  5. Disconnect the K73 telematics communication interface module coax at the T4G cellular phone, navigation, and digital radio antenna.
  6. Test the coax cable between the K73 telematics communication interface control module and the T4G cellular phone, navigation, and digital radio antenna. Refer to component testing below. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test
  7. Test or replace the T4G cellular phone, navigation, and digital radio antenna.

with Navigation Radio

  1. Ignition OFF, disconnect the coax cable at the T15 navigation signal antenna splitter.
  2. Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable), connect the EL-49903 GM OnStar antenna diagnostic tool kit to the navigation signal splitter. Place the test antenna on the roof of the vehicle, ignition ON.
  3. Verify that the customer GPS concern is still present. If the GPS concern is not present Ignition OFF, disconnect the EL-49903 GM OnStar antenna diagnostic tool kit from the K73 telematics communication interface control module. Connect the GPS, T15 navigation antenna signal splitter, and cellular coax cable connector at the K73 telematics communication interface control module. Disconnect the coax cable at the T4G cellular phone, navigation and digital radio antenna. Test the coax cable between the T15 navigation antenna signal splitter and the T4G cellular phone, navigation and digital radio antenna. Refer to Component Testing below. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test Replace the T4G cellular phone, navigation and digital radio antenna. If the GPS concern is still present
  4. Ignition OFF, disconnect the coax cable between the T15 navigation antenna signal splitter and the K73 telematics communication interface control module.
  5. Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable), connect the EL-49903 GM OnStar antenna diagnostic tool kit to the telematics communication interface module. Place the test antenna on the roof of the vehicle, ignition ON.
  6. Verify that an OnStar advisor can locate the vehicle after performing a blue button press. If the advisor can not locate the vehicle Replace the K73 telematics communication interface control module. If the advisor can locate the vehicle
  7. Ignition OFF.
  8. Test the coax cable between the navigation signal splitter and the K73 telematics communication interface control module. Refer to Component Testing below. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test
  9. Ignition OFF, disconnect the coax cable between the T15 navigation signal splitter and the A11 radio.
  10. Connect the test antenna to the radio and place the test antenna on the roof of the vehicle.
  11. Ignition ON.
  12. Verify that the NO GPS symbol/message is not displayed on the radio. If the NO GPS symbol/message is displayed Replace the A11 Radio If the NO GPS symbol/message is not displayed
  13. Ignition OFF.
  14. Test the coax cable between the T15 navigation antenna signal splitter and the A11 radio. Refer to Component Testing below. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test
  15. Replace the T15 navigation antenna signal splitter.
CAUTIONRefer to Test Probe Caution .

Note. Before testing the coax cable, check the cable exterior for being pinched, cut, damaged, or having loose connections at the components, which can cause reception issues. To prevent false reading when testing the center coax terminals, use care not to ground the test probe on the outer housing/shield. The vehicle may be equipped with sectioned coax. Test each section and replace only the faulty section, not the entire length of coax.

Coax Cable Test

  1. Ignition OFF, disconnect the coax cable at both components.
  2. Test for less than 5 ohms between the coax cable center terminal end to end. If 5 ohms or greater Replace the coax cable. If less than 5 ohms
  3. Test for greater than 5 ohms between the coax cable outer shield end to end. If 5 ohms or greater Replace the coax cable. If less than 5 ohms
  4. Test for infinite resistance between the coax cable center terminal and the coax cable outer shield. If less than infinite resistance Replace the coax cable. If infinite resistance
  5. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Navigation Signal Splitter Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Radio Antenna Base Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  3. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for telematics communication interface control module replacement, programming, and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
10 V ReferenceB2476 04
Control Terminal 6112
Control Terminal 7112
Signal Terminal 333B2476 59, B2482 00
GroundB2476 04
1. OnStar® LED Inoperative 2. LED Illuminated At All Times 3. OnStar® Buttons Inoperative

Circuit Description

The OnStar® status LEDs are located in the inside rearview mirror telematic button assembly. The green LED is illuminated when the system is ON and operating normally. When the green LED is green and flashing, it is an indication that a call is in progress. When the red LED is illuminated, a system malfunction is present. In the event there is a system malfunction and the OnStar® system is still able to make a call, the LED will flash red during the call. The OnStar® LEDs are controlled by the telematics communication interface control module via the keypad green LED control circuit and the keypad red LED control circuit.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. If the green LED is off with the ignition ON and the LED functions correctly when commanded with the scan tool, contact the OnStar Center to confirm the vehicle has a current subscription.

  1. Ignition ON.
  2. Verify DTC U0078 is not set. If DTC U0078 is set Refer to «DTC U0078»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#data-communications-system) If DTC U0078 is not set
  3. Verify that the green LED turns ON and OFF when commanding the K73 telematics communication interface control module green indicator ON and OFF with a scan tool. If the green LED does not turn ON and OFF Refer to Circuit/System Testing - Green LED Test below. If the green LED turns ON and OFF
  4. Verify that the red LED turns ON and OFF when commanding the K73 telematics communication interface control module red indicator ON and OFF with a scan tool. If the red LED does not turn ON and OFF Refer to Circuit/System Testing - Red LED Test below. If the red LED turns ON and OFF
  5. All OK.

Green LED Test

  1. Ignition OFF, and all vehicle systems OFF, disconnect the harness connector at the A10 inside rearview mirror. It may take up to 2 minutes for all vehicle systems to power down. Doors closed, courtesy lamps OFF.
  2. Test for less than 10 ohms between the ground circuit terminal 5 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
  3. Ignition ON.
  4. Test for less than 1 V between the control circuit terminal 6 and ground while commanding the K73 telematics communication interface control module green indicator OFF with a scan tool. If 1 V or greater Ignition OFF, disconnect the X1 harness connector at the K73 telematics communication interface control module, ignition ON. Test for less than 1 V between the control circuit terminal 6 and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K73 telematics communication interface control module. If less than 1 V
  5. Test for greater than 8 V between the control circuit terminal 6 and ground while commanding the K73 telematics communication interface control module green indicator ON with a scan tool. If 8 V or less Ignition OFF, disconnect the X1 harness connector at the K73 telematics communication interface control module. Test for infinite resistance between the control circuit terminal 6 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K73 telematics communication interface control module. If greater than 8 V
  6. Test or replace the A10 inside rearview mirror.

Red LED Test

  1. Ignition OFF, and all vehicle systems OFF, disconnect the harness connector at the A10 inside rearview mirror. It may take up to 2 minutes for all vehicle systems to power down. Doors closed, courtesy lamps OFF.
  2. Test for less than 10 ohms between the ground circuit terminal 5 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
  3. Ignition ON.
  4. Test for less than 1 V between the control circuit terminal 7 and ground while commanding the K73 telematics communication interface control module red indicator OFF with a scan tool. If 1 V or greater Ignition OFF, disconnect the X1 harness connector at the K73 telematics communication interface control module, ignition ON. Test for less than 1 V between the control circuit terminal 7 and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K73 telematics communication interface control module. If less than 1 V
  5. Test for greater than 8 V between the control circuit terminal 7 and ground while commanding the K73 telematics communication interface control module red indicator ON with a scan tool. If 8 V or less Ignition OFF, disconnect the X1 harness connector at the K73 telematics communication interface control module. Test for infinite resistance between the control circuit terminal 7 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K73 telematics communication interface control module. If greater than 8 V
  6. Test or replace the A10 inside rearview mirror.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Inside Rearview Mirror Replacement»(/buick/lacrosse/ii-2009-2013/remont/mirrors/#mirror-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for telematics communication interface control module replacement, programming and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The telematics communication interface control module has the capability of commanding the horn, initiating door lock/unlock, or operating the exterior lamps using the serial data circuits. These functions are commanded by the OnStar® Call Center per a customer request.

The customer concern may have been due to a lack of cellular service in a given area, or a failure in the National Cellular Network infrastructure that has since been corrected.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. It is necessary to inform the OnStar® Call Center advisor that this call is for vehicle diagnostic purposes. It is necessary to have the vehicle in an open outside area where a cellular call can be successfully placed and GPS data can be received from satellites.

  1. Ignition ON.
  2. Verify that the horn, lights, and the door locks on the vehicle operate properly. If an applicable vehicle system does not operate properly Refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) . If all applicable vehicle systems operate properly
  3. Verify that a call can be successfully placed to the OnStar Call Center by pressing the blue OnStar button. If unable to contact the OnStar® call center Refer to «Unable to Contact OnStar Call Center»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) If able to contact the OnStar Call Center
  4. Verify with the OnStar advisor that all remote functions (door locks, lights, and horn) work. If the remote functions do not operate when requested Replace the K73 telematics communication interface control module If the remote functions operate when requested
  5. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for telematics communication interface control module replacement, programming and setup.

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
10 V ReferenceB2476 04
Signal Terminal 3221B2476 59, B2482 00
GroundB2476 04
1. Red LED Illuminated At All Times 2. OnStar® Buttons Inoperative

The OnStar® button assembly consists of 3 buttons: Call/Answer, OnStar® Call Center, and OnStar® Emergency. The telematics communication interface control module supplies the OnStar® button assembly with 10 V via the keypad supply voltage circuit. Each of the buttons, when pressed, completes the circuit across a resistor allowing a specific voltage to be returned to the telematics communication interface control module over the keypad signal circuit. Depending upon the voltage range returned, the telematics communication interface control module is able to identify which button has been activated.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. Contact the OnStar® Call Center first before pressing the emergency button in order to notify them of the test.

  1. Ignition ON.
  2. Verify that each button of the S51 telematics button assembly operates normally by pressing each button individually. If none of the buttons operate normally Refer to Circuit/System Testing below. If some, but not all, of the buttons operate normally Test or replace the A10 inside rearview mirror. If all of the buttons operate normally
  3. All OK.
  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the A10 inside rearview mirror. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 15 ohms between the ground circuit terminal 5 and ground. If 15 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 15 ohms
  3. Ignition ON.
  4. Test for 9.5-10.5 V between the 10 V reference circuit terminal 4 and ground. If less than 9.5 V Ignition OFF, disconnect the harness connector at the K73 telematics communication interface control module. Test for infinite resistance between the 10 V reference circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the 10 V reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K73 telematics communication interface control module. If greater than 10.5 V Ignition OFF, disconnect the harness connector at the K73 telematics communication interface control module, ignition ON. Test for less than 1 V between the 10 V reference circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K73 telematics communication interface control module. If between 9.5-10.5 V
  5. Ignition OFF.
  6. Test for 500-900 ohms between the signal circuit terminal 3 and ground. If less than 500 ohms Disconnect the X1 harness connector at the K73 telematics communication interface control module. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K73 telematics communication interface control module. If greater than 900 ohms Disconnect the X1 harness connector at the K73 telematics communication interface control module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K73 telematics communication interface control module. If between 500-900 ohms
  7. Test or replace the A10 inside rearview mirror.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Inside Rearview Mirror Replacement»(/buick/lacrosse/ii-2009-2013/remont/mirrors/#mirror-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for telematics communication interface control module replacement, programming and setup.

OnStar Steering Wheel Control Functions Malfunction

Some vehicles equipped with the OnStar® system have the capability of accessing voice mailboxes and other automated phone systems by means of the steering wheel controls, while the OnStar® Personal Calling feature is in use. If the "Talk" or "Mute" button (depending upon the vehicle) on the steering wheel controls is depressed during an OnStar® Personal Calling call, the telematics communication interface control module receives the message on the serial data bus from either the radio or body control module. This message is interpreted as a request to turn any spoken numbers into dual tone multi-frequency tones to be delivered over the airwaves to the phone system the user is communicating with. Complete instructions for operation of these features can be found in the information provided to the customer with the OnStar® system.

The steering wheel controls are a resistor network that consist of multiple momentary contact switches and a series of resistors. The switches and resistor network are arranged so that each switch has a different resistance value. When a switch is pressed, a voltage drop occurs in the resistor network, which produces a specific voltage value unique to the switch selected, to be interpreted by either the radio or BCM. In the event the OnStar® steering wheel control functions are inoperative, technicians should refer to Steering Wheel Controls Malfunction , to begin diagnosis of the steering wheel control concern.

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Radio Controls B+U0257, 1, 2, 32, 4
Radio Display B+U0257, 1, 2, 3U0257, 1, 3, 4
Remote Enable CircuitU0257, 1, 4U0257, 1, 4
Radio Controls ResetU0257, 1, 2
Radio Controls WakeupU0257, 1, 2U0257, 1, 2
Radio Display ResetU0257, 1
CGI Serial Data +U0257, 1, 2U0257, 1, 2U0257, 1, 2
CGI Serial DataU0257, 1, 2U0257, 1, 2U0257, 1, 2
Touch Screen Serial Data +U0257, 1U0257, 1U0257, 1
Touch Screen Serial DataU0257, 1U0257, 1
Radio Controls ground2
Radio Display Ground
1. Display Inoperative 2. Controls inoperative 3. Fault affects multiple components, dependant on vehicle equipment additional communication DTCs may be set 4. Fault may affect one or more components, dependant on fault location

The radio/HVAC controls are supplied battery voltage and ground. The radio controls the power state of the controls via a wake up circuit. Communications between the radio controls and the radio are through the CGI serial data circuits.

Communications between the HVAC controls and the HVAC control module are on a separate LIN circuit. The HVAC control module communicates status information to the radio via GMLAN for HVAC information display.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, A11 radio ON.
  2. Verify that all radio controls operate and perform the correct function. If some, but not all, controls operate normally. Replace the A20 radio/HVAC controls. If all controls are inoperative. Refer to Circuit/System Testing below. If all radio controls operate and perform the correct function.
  3. All OK.
  1. Ignition OFF, disconnect the harness connector at the A20 radio/HVAC controls.
  2. Test for less than 10 ohms between the ground circuit terminal 17 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
  3. Test for less than 20 ohms between the data shield circuit terminal 3 and ground. If 20 ohms or greater Ignition OFF, disconnect the X1 connector at the A11 radio. Test for less than 2 ohms in the data shield circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If less than 20 ohms
  4. Verify that a test lamp illuminates between the B+ circuit terminal 10 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, refer to «Power Mode Mismatch»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures) . If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the A20 radio/HVAC controls. If the test lamp illuminates.
  5. Ignition ON.
  6. Test for 2-3 V between the serial data circuit terminals listed below and ground. terminal 1 terminal 2 If less than 2 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Test for infinite resistance between the serial data circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the serial data circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If greater than 3 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the serial data circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If between 2-3 V
  7. Test for less than 1 V between the control circuit terminals listed below and ground. terminal 4 terminal 15 If greater than 1 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If less than 1 V
  8. Ignition OFF, disconnect the X1 harness connector at the A11 radio.
  9. Test for infinite resistance between the control circuit terminals listed below and ground. A20 radio/HVAC controls terminal 4 A20 radio/HVAC controls terminal 15 If less than infinite resistance, Repair the short to ground on the circuit. If infinite resistance
  10. Test for less than 2 ohms between the control circuits listed below. A20 radio/HVAC controls terminal 4 and the A11 radio terminal 13 X1 A20 radio/HVAC controls terminal 15 and the A11 radio terminal 27 X1 If 2 ohms or greater Repair the open/high resistance in the circuit. If less than 2 ohms.
  11. Replace the A20 radio/HVAC controls. Connect all harness connectors.
  12. Ignition ON, radio ON.
  13. Verify that all radio controls operate and perform the correct function. If the radio controls still malfunction. Replace the A11 radio. If all radio controls operate and perform the correct function.
  14. All OK

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Radio Control Assembly Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Radio Controls B+U0257, 1, 2, 32, 4
Radio Display B+U0257, 1, 2, 3U0257, 1, 3, 4
Remote Enable CircuitU0257, 1, 4U0257, 1, 4
Radio Controls ResetU0257, 1, 2
Radio Controls WakeupU0257, 1, 2U0257, 1, 2
Radio Display ResetU0257, 1
CGI Serial Data +U0257, 1, 2U0257, 1, 2U0257, 1, 2
CGI Serial DataU0257, 1, 2U0257, 1, 2U0257, 1, 2
Touch Screen Serial Data +U0257, 1U0257, 1U0257, 1
Touch Screen Serial DataU0257, 1U0257, 1
Radio Controls ground2
Radio Display Ground
1. Display Inoperative 2. Controls inoperative 3. Fault affects multiple components, dependant on vehicle equipment additional communication DTCs may be set 4. Fault may affect one or more components, dependant on fault location

The radio info display module is supplied battery voltage and ground. The radio controls the power state of the display through the remote enable circuit, which is also used to control the power state of other infotainment devices. The info display module receives digital video data from the radio for on-screen display information through the video signal circuits. The radio communicates with the info display module over the touch screen serial data circuits for touch screen inputs and backlighting dimming level.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Verify DTC B1265 is not set. If DTC B1265 is set. Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . If DTC B1265 is not set.
  2. Ignition ON, radio ON.
  3. Verify the P17 info display module turns on and information is shown on the display. If the P17 info display module does not turn on, or information is not shown in the display. Refer to Circuit/System Testing below. If the P17 info display module turns on and information is shown on the display.
  4. All OK.
  1. Ignition OFF.
  2. Verify the video interface cable is properly connected at the P17 info display module X2 and A11 radio X4 connections and there is no damage to the cable or connections. If connection problems or cable damage is noted. Perform the appropriate repair or replacement to correct any issues. If no issues are found with the video interface cable.
  3. Disconnect the X1 harness connector at the P17 info display module.
  4. Test for less than 10 ohms between the ground circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
  5. Test for less than 20 ohms between the data shield circuit terminal 7 and ground. If 20 ohms or greater Ignition OFF, disconnect the X3 connector at the A11 radio. Test for less than 2 ohms in the data shield circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If less than 20 ohms
  6. Verify that a test lamp illuminates between the B+ circuit terminal 1 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, refer to «Power Mode Mismatch»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures) . If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the P17 info display module. If the test lamp illuminates.
  7. Ignition ON, radio ON.
  8. Verify that a test lamp illuminates between the control circuit terminal 6 and ground. If the test lamp does not illuminate. Ignition OFF, disconnect the X1 harness connector at the A11 radio. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If the test lamp illuminates.
  9. Test for 2-3 V between the data circuit terminals listed below and ground. terminal 4 terminal 8 If less than 2 V Ignition OFF, disconnect the X3 harness connector at the A11 radio. Test for infinite resistance between the data circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the data circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If greater than 3 V Ignition OFF, disconnect the X3 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the data circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If between 2-3 V
  10. Ignition ON.
  11. Test for less than 1 V between the control circuit terminal 5 and ground. If greater than 1 V Ignition OFF, disconnect the X3 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If less than 1 V
  12. Ignition OFF, disconnect the X3 harness connector at the A11 radio.
  13. Test for infinite resistance between the P17 info display module control circuit terminal 5 X1 and ground. If less than infinite resistance, Repair the short to ground on the circuit. If infinite resistance
  14. Test for less than 2 ohms between the P17 info display module control circuit terminal 5 X1 and the A11 radio control circuit terminal 10 X3. If 2 ohms or greater Repair the open/high resistance in the circuit. If less than 2 ohms.
  15. Replace the video interface cable.
  16. Connect all harness connectors.
  17. Ignition ON, radio ON.
  18. Verify the P17 info display module turns on and information is shown on the display. If the P17 info display module does not turn on, or information is not shown in the display. Replace the P17 information display module. Ignition ON, radio ON. Verify the P17 info display module turns on and information is shown on the display. If the information display malfunctions, replace the A11 radio. If the info display module turns on and information is shown on the display. All OK. If the info display module turns on and information is shown on the display.
  19. All OK

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Driver Information Display Replacement (With UAG)»(/buick/lacrosse/ii-2009-2013/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges) , «Driver Information Display Replacement (With UDT)»(/buick/lacrosse/ii-2009-2013/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Radio Antenna CoaxB125A 02B125A 041
Ground1
1. May exhibit possible AM/FM interference

AM and FM radio reception is dependent on the following components

  1. Radio antenna in the rear glass
  2. Radio antenna module
  3. Coax cable between the radio antenna and the radio antenna module
  4. Radio

The antenna module receives both AM and FM signals from the rear glass antenna. The radio antenna module is enabled when the radio is turned on. The radio provides battery voltage to the antenna module using the center conductor of the antenna coaxial cable. When a 12 V signal is seen by the module on the center conductor of the antenna coax, both AM and FM signals are amplified.

Poor AM and FM radio reception is dependent on multiple influences, some of which may not be vehicle related. Areas which have high RF traffic or block the signal path may cause a degradation in radio reception. Radio reception may also be influenced by items within the vehicle, but not part of the radio system. Such examples are aftermarket electrical accessories or other items which may generated noise in the vehicle electrical system. Aftermarket window tinting, especially when there is a metallic in the film, may reduce radio reception.

AM reception is highly dependent on the antenna module receiving battery voltage from the radio and being properly grounded. The antenna module has a built in antenna amplifier that boosts both AM and FM reception. When the antenna module does not receive power, AM stations may not be received and FM reception will be limited. If the module is not properly grounded, excessive interference in the signal may occur, or reception may be limited.

  1. Ignition ON.
  2. Battery voltage must be between 9-16 V.

B125A 02

The radio detects a short to ground in the antenna signal circuit center conductor.

B125A 04

The radio detects an open in the antenna signal circuit center conductor.

Radio reception may be poor or not available.

  1. The condition responsible for setting the DTC no longer exists.
  2. A history DTC will clears after 50 consecutive malfunction-free ignition cycles have occurred.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#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 radio antenna coax from the A11 radio and from the K46 radio antenna module.
  2. Test for infinite resistance between the antenna coax center terminal and ground. If less than the specified value, replace the antenna coax.
  3. Test for less than 5 ohms on the antenna coax center circuit from end to end. If greater than the specified range, replace the antenna coax.
  4. Ignition ON, test for less than 1 V between the antenna coax center terminal and ground. If greater than the specified range, replace the antenna coax.
  5. Test for infinite resistance between the coax center terminal and the outer shield. If less than the specified value, replace the antenna coax.
  6. Connect the antenna coax to the A11 radio. Test for 12-15 V between the antenna coax center terminal and ground at the K46 radio antenna module connector. If not within the specified range, replace the A11 radio.
  7. If all circuits test normal, replace the K46 radio antenna module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for radio replacement, setup, and programming

Speaker Replacement Reference

Speaker Replacement Reference

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Amplifier B+11
Amplifier Center Audio Signal222, 32
Amplifier LF Audio Signal222, 32
Amplifier LR Audio Signal222, 32
Amplifier RF Audio Signal222, 32
Amplifier RR Audio Signal222, 32
Amplifier Subwoofer Audio Signal222, 32
Radio Center Audio Signal (if equipped)222, 32
Radio LF Audio SignalB1025 02*, 2B1025 02*, 2B1025 02*, 2, 32
Radio LR Audio SignalB1035 02*, 2B1035 02*, 2B1035 02*, 2, 32
Radio RF Audio SignalB1045 02*, 2B1045 02*, 2B1045 02*, 2, 32
Radio RR Audio SignalB1055 02*, 2B1055 02*, 2B1055 02*, 2, 32
Radio Subwoofer Audio Signal (if equipped)222, 32
Remote Enable SignalB1265 02, 11, 4
Amplifier ControlB1287 02B1287 04B1287 01
Amplifier Ground11
1. Audio inoperative, no sound from all speakers. 2. No or reduced audio from speaker(s) on the affected audio circuit. 3. Noticeable audio distortion may be present. 4. Fault may affect one or more components, dependant on vehicle equipment. * When equipped with an amplifier, the radio does not set this DTC.

Each of the audio output channel circuits (+) and (-), at the radio and audio amplifier have a DC bias voltage that is approximately one half of battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5 V DC. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound. The frequency (Hz) of the AC voltage signal is directly related to the frequency of the input (audio source playing) to the audio system. Both the DC bias voltage and the AC voltage signals are needed for the audio system to properly produce sound.

  1. Improper speaker mounting or loose trim may cause an audible buzz or distortion. Inspect the appropriate speaker and the surrounding interior trim for proper and secure mounting. The EL-50334-6 Audio System Diagnostic CD contains audio tracks that can be used to duplicate and isolate such concerns. Tracks 11 and 12 contain audio sweep tones for testing for speaker and grill rattles. If the speaker or surrounding interior trim is found to be loose or improperly secured, correctly secure the item.
  2. The test tones on the CD may be copied to a USB drive or other device to use during testing.
  3. When equipped with an amplifier, it is possible for some individual circuit faults to affect more than one speakers operation. Perform diagnostic tests in the sequence listed to avoid misdiagnosis.
  4. The amplifier control circuit will measure less than 1 V when the mute function is OFF, and approximately 8 V DC when at full mute. When mute is active, the radio stops sending the varying AC voltage to the amplifier/speakers.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-50334-50 USB Cable and Adapter Kit

Without Amplifier

  1. Ignition ON, A11 radio ON, mute OFF.
  2. Verify clear audio is heard from each speaker, adjusting fade and balance controls to test each speaker individually. If audio is inoperative from one or more speakers, or the audio emitted is not clear Refer to Speaker Malfunction - without Amplifier below. If clear audio is heard from all speakers
  3. All OK.

With Amplifier

  1. Ignition ON, A11 radio ON, mute OFF.
  2. Verify clear audio is heard from each speaker, adjusting fade and balance controls to test each speaker individually. If audio is inoperative from one or more speakers, or the audio emitted is not clear Refer to Speaker Malfunction - with Amplifier below. If clear audio is heard from all speakers
  3. All OK.

Speaker Malfunction - without Amplifier

  1. Ignition OFF, disconnect the harness connector at the appropriate P19 speaker. Ignition ON, radio ON, mute OFF.
  2. Test for 5-7 V between each audio signal circuit terminal 1 and terminal 2 and ground. If less than 5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If greater than 7 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If between 5-7 V
  3. Mute OFF, play track number three (50 Hz bass test tone) from the EL-50334-50 audio test CD.
  4. Test for 49-51 Hz AC between each signal circuit terminal 1 and terminal 2 and ground. If not between 49-51 Hz AC Replace the A11 radio. If between 49-51 Hz AC
  5. Test or replace the P19 speaker.

Speaker Malfunction- with Amplifier

  1. Ignition OFF, disconnect the X1 harness connector at the T3 audio amplifier.
  2. Test for less than 10 ohms between the ground circuit terminal 8 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
  3. Verify that a test lamp illuminates between the B+ circuit terminal 4 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, refer to «Power Mode Mismatch»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures) . If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the T3 audio amplifier. If the test lamp illuminates
  4. Disconnect the X3 harness connector at the T3 audio amplifier.
  5. Verify a test lamp does NOT illuminate between the control circuit terminal 13 and ground. If the test lamp illuminates Disconnect the X1 harness at the A11 radio. Verify a test lamp does not illuminate between the control circuit and ground. If the test lamp illuminates, repair the short to voltage on the circuit. If the test lamp does not illuminate, replace the A11 radio. If the test lamp does not illuminate
  6. Ignition ON, A11 radio ON.
  7. Verify a test lamp illuminates between the control circuit terminal 13 and ground. If the test lamp does not illuminate Ignition OFF. Disconnect the X1 harness at the A11 radio. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If the test lamp illuminates
  8. A11 Radio ON, mute ON.
  9. Test for 7.5-8.5 V between the control circuit terminal 6 and ground. If greater than 8.5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If less than 7.5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If between 7.5-8.5 V
  10. A11 Radio ON, mute OFF.
  11. Test for less than 1 V between the control circuit terminal 6 and ground. If greater than 1 V Replace the A11 radio. If less than 1 V
  12. Test for 5-7 V between the signal circuit terminals listed below and ground: Left front low level audio signal (+) terminal 9 Left front low level audio signal (-) terminal 1 Right front low level audio signal (+) terminal 10 Right front low level audio signal (-) terminal 2 Left rear low level audio signal (+) terminal 11 Left rear low level audio signal (-) terminal 3 Right rear low level audio signal (+) terminal 12 Right rear low level audio signal (-) terminal 4 Center channel low level audio signal (+) terminal 7 (if equipped) Center channel low level audio signal (-) terminal 15 (if equipped) Subwoofer low level audio signal (+) terminal 8 (if equipped) Subwoofer low level audio signal (-) terminal 16 (if equipped) If less than 5 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If greater than 7 V Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If between 5-7 V
  13. Mute OFF, play track number three (50 Hz bass test tone) from the EL-50334-50 audio test CD.
  14. Test for 49-51 Hz AC between the audio signal circuit terminals listed below and ground. Left front low level audio signal (+) terminal 9 Left front low level audio signal (-) terminal 1 Right front low level audio signal (+) terminal 10 Right front low level audio signal (-) terminal 2 Left rear low level audio signal (+) terminal 11 Left rear low level audio signal (-) terminal 3 Right rear low level audio signal (+) terminal 12 Right rear low level audio signal (-) terminal 4 Center channel low level audio signal (+) terminal 7 (if equipped) Center channel low level audio signal (-) terminal 15 (if equipped) Subwoofer low level audio signal (+) terminal 8 (if equipped) Subwoofer low level audio signal (-) terminal 16 (if equipped) If not between 49-51 Hz AC Replace the A11 radio. If between 49-51 Hz AC
  15. Ignition OFF, connect all harness connectors.
  16. Disconnect the harness connector at the appropriate P19 speaker. Ignition ON, A11 radio ON.
  17. Test for 5-7 V between the appropriate speaker signal terminals listed below and ground: Door speakers, front tweeter speakers, rear compartment speakers, or center I/P speaker: speaker control (-) circuit terminal 1 Door speakers, front tweeter speakers, rear compartment speakers, or center I/P speaker: speaker control (+) circuit terminal 2 Subwoofer speaker control (-) circuit terminal A Subwoofer speaker control (+) circuit terminal B If less than 5 V Ignition OFF, disconnect the X1 and X2 harness connectors at the T3 audio amplifier. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the T3 audio amplifier. If greater than 7 V Ignition OFF, disconnect the X1 and X2 harness connectors at the T3 audio amplifier. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the T3 audio amplifier. If between 5-7 V
  18. Mute OFF, play track number three (50 Hz bass test tone) from the test CD.
  19. Test for 49-51 Hz AC between the appropriate speaker signal terminals listed below and ground: Door speakers, front tweeter speakers, rear compartment speakers, or center I/P speaker: speaker control (-) circuit terminal 1 Door speakers, front tweeter speakers, rear compartment speakers, or center I/P speaker: speaker control (+) circuit terminal 2 Subwoofer speaker control (-) circuit terminal A Subwoofer speaker control (+) circuit terminal B If not between 49-51 Hz AC Replace the T3 audio amplifier. If between 49-51 Hz AC
  20. Test or replace the P19 speaker.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Speaker Replacement Reference»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__speaker-replacement-reference)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for amplifier or radio replacement, programming and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The Telematics Communication Interface Control Module is a cellular device that allows the user to communicate data and voice signals over the national cellular network. When an OnStar keypress is made, the Telematics Communication Interface Control Module activates and connects the system to the cellular carriers communication system by interacting with the national cellular infrastructure. The module sends and receives all cellular communications over the cellular phone and navigation antenna and cellular antenna coax.

  1. The customer concern may have been due to a lack of cellular service in a given area. A failure in the National Cellular Network infrastructure at the time of the customers failed connection that has since been repaired may also have been the cause.
  2. If an OnStar® emergency call is able to successfully connect the vehicle to the OnStar® Call Center when an OnStar® Call Center button press is not, there may be a failure in the ability of the OnStar® system in the vehicle to be recognized by the local cellular carrier.
  3. If the prompt "OnStar® request ended" is heard, without pressing the white dot button at the end of the OnStar® keypress, the OnStar® system at one time has made a successful cellular connection, but was unable to complete the call.
  4. It is important to have the vehicle in an open outside area where a cellular call can be successfully placed and GPS data can be received from satellites.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-49903 GM OnStar Antenna Diagnostic Tool Kit

Note. The following verification requires the vehicle to be outside with an unobstructed view of the southern sky. Allow 5 minutes after turning the ignition ON for the GPS satellites to acquire vehicle signal.

  1. Ignition ON.
  2. Verify that DTC B2470 is not set. If DTC B2470 is set Refer to «DTC B2470»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) If DTC B2470 is not set
  3. Verify that a call can be successfully placed to the OnStar Call Center by pressing the blue OnStar button. If unable to connect with the OnStar Call Center. Refer to Circuit/System Testing below. If able to connect with the OnStar Call Center
  4. All OK.

Note. The vehicle may be equipped with sectioned coax. Test each section and replace only the faulty section, not the entire length of coax. The following verification requires the vehicle to be outside with an unobstructed view of the southern sky. Allow 5 minutes after turning the ignition ON for the GPS satellites to acquire vehicle signal.

Without Navigation Radio

  1. Ignition OFF and all vehicle systems OFF, disconnect the GPS and cellular coax cable connector at the K73 Telematics Communication Interface Control Module. It may take up to 2 minutes for all vehicle systems to power down.
  2. Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable), connect the EL-49903 GM OnStar antenna diagnostic tool kit to the K73 Telematics Communication Interface Control Module.
  3. Ignition ON, wait 5 minutes.
  4. Verify that a call can be successfully placed to the OnStar Call Center by pressing the blue OnStar button. If unable to connect with the OnStar Call Center Test or replace the K73 Telematics Communication Interface Control Module. If able to connect with the OnStar Call Center
  5. Ignition OFF, disconnect the EL-49903 GM OnStar antenna diagnostic tool kit from the K73 Telematics Communication Interface Control Module
  6. Test the coax cable between the K73 Telematics Communication Interface Control Module and the T4G Cellular Phone, Navigation, and Digital Radio Antenna. Refer to Component Testing below. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test
  7. Test or replace the T4G Cellular Phone, Navigation, and Digital Radio Antenna.

With Navigation Radio

  1. Ignition OFF and all vehicle systems OFF, disconnect the GPS and cellular coax cable connector at the K73 Telematics Communication Interface Control Module. It may take up to 2 minutes for all vehicle systems to power down.
  2. Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable), connect the EL-49903 GM OnStar antenna diagnostic tool kit to the K73 Telematics Communication Interface Control Module.
  3. Ignition ON, wait 5 minutes.
  4. Verify that a call can be successfully placed to the OnStar Call Center by pressing the blue OnStar button. If unable to connect with the OnStar Call Center Test or replace the K73 Telematics Communication Interface Control Module. If able to connect with the OnStar Call Center
  5. Ignition OFF, disconnect the EL-49903 from the K73 Telematics Communication Interface Control Module.
  6. Test the coax cable between the K73 Telematics Communication Interface Control Module and the T15 Navigation Antenna Signal Splitter. Refer to Component Testing below. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test
  7. Test the coax cable between the T15 Navigation Antenna Signal Splitter and the T4G Cellular Phone, Navigation, and Digital Radio Antenna. If the coax cable does not pass the test Replace the coax cable. If the coax cable passes the test
  8. Test or replace the T15 navigation and signal splitter.
  9. Verify that a call can be successfully placed to the OnStar Call Center by pressing the blue OnStar button. If unable to connect with the OnStar Call Center Test or replace the T4G Cellular Phone, Navigation, and Digital Radio Antenna. If able to connect with the OnStar Call Center
  10. All OK.
CAUTIONRefer to Test Probe Caution .

Note. Before testing the coax cable, check the cable exterior for being pinched, cut, damaged, or having loose connections at the components, which can cause reception issues. To prevent false reading when testing the center coax terminals, use care not to ground the test probe on the outer housing/shield.

Coax Cable Test

  1. Ignition OFF, disconnect the coax cable at both components.
  2. Test for less than 5 ohms between the coax cable center terminal end to end. If 5 ohms or greater Replace the coax cable. If less than 5 ohms
  3. Test for greater than 5 ohms between the coax cable outer shield end to end. If 5 ohms or greater Replace the coax cable. If less than 5 ohms
  4. Test for infinite resistance between the coax cable center terminal and the coax cable outer shield. If less than infinite resistance Replace the coax cable. If infinite resistance
  5. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Navigation Signal Splitter Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Radio Antenna Base Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  3. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Telematics Communication Interface Control Module replacement, programming and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Video Display B+21
Remote Enable Control CircuitB1265 02, 345
DVD Audio Common Signal (-)666
Left DVD Audio Signal (+)777
Right DVD Audio Signal (+)888
DVD Video Signal (+)997
DVD Video Signal (-)999, 10
Infrared Remote Signal (+)111111
Infrared Remote Signal (-)111111
Video Mode SignalB1288 02, 12B1288 04, 12B1288 01, 12
Video Bright SignalB1289 02, 13B1289 04, 13B1289 01, 13
Ground Terminal 81
Ground Terminal 141
1. One or both seatback displays inoperative 2. Both seatback displays inoperative 3. All infotainment devices controlled by circuit inoperative, no sound from speakers 4. One or more infotainment devices controlled by circuit inoperative 5. Power state of all infotainment devices controlled by circuit cannot be controlled by radio 6. No or distorted audio heard in wireless headphones 7. No or distorted left channel audio heard in wireless headphones 8. No or distorted right channel audio heard in wireless headphones 9. No or distorted image in seatback display 10. Serious damage to radio can occur 11. Infrared remote control inoperative 12. Seatback display mode cannot be controlled/changed 13. Seatback display brightness cannot be controlled/adjusted

The rear seat entertainment (RSE) system utilizes the vehicle radio to play DVD movies and transmit video signals to the seatback displays. When the radio is turned ON, the seatback displays receive a voltage signal from the radio via the remote enable signal circuit indicating the system status. Discreet output circuits from the radio are used to transmit the DVD images to each of the displays. The radio utilizes discreet mode control circuits to each display to control the screen display mode via a pulse width modulated signal. A single brightness control circuit is used by the radio to control the display screen brightness for both displays via a pulse width modulated signal.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Ignition ON, radio ON, DVD playing.
  2. Verify that the Rear Seat Entertainment System audio/video operates. If the Rear Seat Entertainment System is inoperative. Refer to Circuit/System Testing below. If the Rear Seat Entertainment System operates.
  3. Verify that the remote control functions properly. If the remote control is inoperative. Refer to «Video Entertainment System Remote Control Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If the remote control operates.
  4. Verify that each headphone functions properly. If one or more of the headphones are inoperative. Refer to «Video Entertainment System Wireless Headphone Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If all headphones operate.
  5. All OK.
  1. Ignition OFF, disconnect the harness connector at the appropriate DVD display.
  2. Test for less than 10 ohms between the ground circuit terminals listed below and ground. Ground terminal 8 Ground terminal 14 If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
  3. Verify a test lamp illuminates between the B+ circuit terminal 1 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, refer to «Power Mode Mismatch»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures) . If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the appropriate P22 seatback video display. If the test lamp illuminates
  4. Verify a test lamp does NOT illuminate between the control circuit terminal 2 and ground. If the test lamp illuminates Disconnect the X1 harness at the A11 radio. Verify a test lamp does not illuminate between the control circuit and ground. If the test lamp illuminates, repair the short to voltage on the circuit. If the test lamp does not illuminate, replace the A11 radio. If the test lamp does not illuminate
  5. Ignition ON, A11 radio ON.
  6. Verify a test lamp illuminates between the control circuit terminal 2 and ground. If the test lamp does not illuminate Ignition OFF. Disconnect the X1 harness at the A11 radio. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If the test lamp illuminates
  7. Ignition ON, radio ON, DVD playing.
  8. Test for 190-210 HZ DC between the control circuit terminal 16 and ground. If not between 190-210 HZ DC. Ignition OFF, disconnect the X2 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If between 190-210 HZ DC.
  9. Test for 190-210 HZ DC between the control circuit terminal 15 and ground. If not between 190-210 HZ DC. Ignition OFF, disconnect the X2 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If between 190-210 HZ DC.
  10. Test for 1-3 V between the signal circuit terminals listed below and ground. terminal 9 terminal 10 If less than 1 V Ignition OFF, disconnect the X2 harness connector at the A11 radio. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If greater than 3 V Ignition OFF, disconnect the X2 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If between 1-3 V
  11. Test normal or replace the appropriate P22 seatback video display.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Video Display Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, setup, and programming
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Video Display B+21
Remote Enable Control CircuitB1265 02, 345
DVD Audio Common Signal (-)666
Left DVD Audio Signal (+)777
Right DVD Audio Signal (+)888
DVD Video Signal (+)997
DVD Video Signal (-)999, 10
Infrared Remote Signal (+)111111
Infrared Remote Signal (-)111111
Video Mode SignalB1288 02, 12B1288 04, 12B1288 01, 12
Video Bright SignalB1289 02, 13B1289 04, 13B1289 01, 13
Ground Terminal 81
Ground Terminal 141
1. One or both seatback displays inoperative 2. Both seatback displays inoperative 3. All infotainment devices controlled by circuit inoperative, no sound from speakers 4. One or more infotainment devices controlled by circuit inoperative 5. Power state of all infotainment devices controlled by circuit cannot be controlled by radio 6. No or distorted audio heard in wireless headphones 7. No or distorted left channel audio heard in wireless headphones 8. No or distorted right channel audio heard in wireless headphones 9. No or distorted image in seatback display 10. Serious damage to radio can occur 11. Infrared remote control inoperative 12. Seatback display mode cannot be controlled/changed 13. Seatback display brightness cannot be controlled/adjusted

The infrared remote signal is used to transmit signals from the rear seat entertainment (RSE) remote control via pulse width modulated (PWM) signals to the radio. When a key on the remote is pressed, the remote control sends an infrared message to the infrared receiver located in the DVD display. The infrared receiver converts these infrared signals into a frequency and sends the message to the radio to perform the appropriate function. Both seatback displays contain receivers for the infrared remote, which are connected to common (+) and (-) signal circuits to the radio.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. Test or replace the remote control batteries before performing the circuit/system verification.

  1. Ignition ON, radio ON, DVD playing.
  2. Verify that the Rear Seat Entertainment System audio/video operates. If the Rear Seat Entertainment System is inoperative. Refer to «Video Entertainment System Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If the Rear Seat Entertainment System operates.
  3. Verify that all remote control functions operate. If some, but not all, controls operate. Replace the remote control. If all controls are inoperative. Replace the remote control. Verify that all remote control functions are working properly. If all controls are inoperative. Refer to Circuit/System Testing below. If all controls operate and perform the correct function. All OK. If all controls operate and perform the correct function.
  4. All OK.
  1. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down
  2. Disconnect the harness connectors at both of the P22 seatback video displays.
  3. Test for less than 10 ohms between the signal (-) circuits terminal 13 and ground at each display. If 10 ohms or greater Ignition OFF, disconnect the X2 connector at the A11 radio. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If less than 10 ohms
  4. Ignition ON, radio ON, DVD playing.
  5. Test for 1-4 V between the signal (+) circuit terminal 12 and ground at each display. If less than 1 V Ignition OFF, disconnect the X2 harness connector at the A11 radio. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If greater than 4 V Ignition OFF, disconnect the X2 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the A11 radio. If between 1-4 V
  6. Ignition OFF. Connect the harness connector at the P22E driver seatback video display.
  7. Ignition ON, radio ON, DVD playing.
  8. Test for 1-4 V between the signal (+) circuit terminal 12 and ground at the P22F passenger seatback video display. If less than 1 V Test or replace the P22E driver seatback video display If greater than 4 V Test or replace the P22E driver seatback video display If between 1-4 V
  9. Test or replace the P22F passenger seatback video display.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Video Display Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/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
Video Display B+21
Remote Enable signal circuitB1265 02, 345
DVD Audio Common Signal (-)666
Left DVD Audio Signal (+)777
Right DVD Audio Signal (+)888
DVD Video Signal (+)997
DVD Video Signal (-)999, 10
Infrared Remote Signal (+)111111
Infrared Remote Signal (-)111111
Video Mode SignalB1288 02, 12B1288 04, 12B1288 01, 12
Video Bright SignalB1289 02, 13B1289 04, 13B1289 01, 13
Ground Terminal 81
Ground Terminal 141
1. One or both seatback displays inoperative 2. Both seatback displays inoperative 3. All infotainment devices controlled by circuit inoperative, no sound from speakers 4. One or more infotainment devices controlled by circuit inoperative 5. Power state of all infotainment devices controlled by circuit cannot be controlled by radio 6. No or distorted audio heard in wireless headphones 7. No or distorted left channel audio heard in wireless headphones 8. No or distorted right channel audio heard in wireless headphones 9. No or distorted image in seatback display 10. Serious damage to radio can occur 11. Infrared remote control inoperative 12. Seatback display mode cannot be controlled/changed 13. Seatback display brightness cannot be controlled/adjusted

The driver seatback DVD display contains the infrared transmitter for the wireless headphones. The audio that is sent over the DVD audio signal circuits is a varying AC voltage. The transmitter processes the signal and transmits the audio signals to the headphones. If the display is in the closed position, the infrared signals will not be available for the operation of the wireless headphones and the remote control.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. Test or replace the headphone batteries before performing the circuit/system verification.

  1. Ignition ON, radio ON, DVD playing.
  2. Verify that the Rear Seat Entertainment System audio/video operates. If the Rear Seat Entertainment System is inoperative. Refer to «Video Entertainment System Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) . If the Rear Seat Entertainment System operates.
  3. Turn ON the wireless headphones.
  4. Verify the power indicator lamp on the wireless headphone illuminates. If the power indicator lamp does not illuminate. Replace the wireless headphones. If the power indicator lamp illuminates.
  5. Ignition ON, radio ON, DVD playing.
  6. Verify that clear audio is heard from each headphone. If audio is heard from some, but not all, headphones. Replace the inoperative headphone. If audio is not heard from any headphones, or the audio heard is not clear. Refer to Circuit/System Testing below. If clear audio is heard from all headphones.
  7. All OK.
  1. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down
  2. Disconnect the harness connector at the P22E driver seatback video display.
  3. Test for less than 25 ohms between the audio signal (-) circuit terminal 5 and ground. If 25 ohms or greater Ignition OFF, disconnect the X1 connector at the A11 radio. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If less than 25 ohms
  4. Ignition ON, radio ON, DVD playing with audio present.
  5. Test for a varying voltage from 10 mV-250 mV AC between the audio signal (+) circuits listed below and ground: terminal 6 terminal 7 If not between 10 mV-250 mV AC and/or not varying Ignition OFF, disconnect the X1 harness connector at the A11 radio. Ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V Ignition OFF. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the A11 radio. If varying from 10 mV-250 mV AC
  6. Test or replace the P22E driver seatback video display.

Perform the Diagnostic Repair Verification after completing the repair.

  1. «Video Display Replacement»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for radio replacement, programming, and setup.
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The telematics communication interface control module is capable of interpreting voice commands received over the cellular microphone circuit. Speech recognition allows the user to speak to one computer in the vehicle, and one reached over the cellular communication network. The module attempts to understand the users command, and responds by speaking back, or by taking the appropriate action, e.g. dialing the phone.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Note. It is necessary to have the vehicle in an open outside area where a cellular call can be successfully placed and GPS data can be received from satellites. The vehicle should be located in a quiet area.

  1. Ignition ON, press the blue OnStar Call button.
  2. Verify that your voice is heard clearly by the OnStar Call center. If your voice can not be heard clearly Refer to «OnStar Microphone Malfunction»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system) If your voice can be heard clearly
  3. Verify that the system responds appropriately to all voice commands by pressing the blue OnStar Call button and attempting to operate the system using multiple voice commands. If the OnStar system does not respond to any voice commands Replace the K73 telematics communication interface control module If the OnStar system responds to some, but not all voice commands Refer to «OnStar Description and Operation»(/buick/lacrosse/ii-2009-2013/remont/entertainment-systems/#cellular-system-entertainment-system-and-navigation-system__onstar-description-and-operation) for tips on proper pronunciation If the OnStar system responds to all voice commands
  4. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for telematics communication interface control module replacement, programming and setup.

Scheme 14

Scheme 14: Mobile Telephone Microphone Replacement
Scheme 14: Mobile Telephone Microphone Replacement
CalloutComponent Name
Preliminary Procedure Remove the roof console. Refer to Roof Console Replacement .
1Mobile Telephone Microphone Procedure Unsnap the microphone from the roof console.

Mobile Telephone Microphone Replacement

Scheme 15

Scheme 15: Communication Interface Module Replacement
Scheme 15: Communication Interface Module Replacement
CalloutComponent Name
1Communication Interface Module Procedure Lower the rear window trim panel speaker opening cover where needed to access the module. Unsnap the module from the bracket. Disconnect the electrical connector. Reprogram the communication interface module after installation. Refer to Control Module References .

Communication Interface Module Replacement

Scheme 16

Scheme 16: Communication Interface Module Battery Replacement
Scheme 16: Communication Interface Module Battery Replacement
CalloutComponent Name
Preliminary Procedure Remove the rear window panel trim. Refer to Rear Window Panel Trim Replacement (with DB3) , Rear Window Panel Trim Replacement (without DB3) , Rear Window Panel Trim Replacement (With HP6) .
1Communication Interface Module Battery Assembly Procedure Unsnap the communication interface module battery from the bracket. Disconnect the electrical connectors. The vehicle communication interface module (VCIM) has a specific set of unique numbers that tie the module to each vehicle. These numbers, the 10-digit station identification and the 11-digit electronic serial number, are used by the National Cellular Network and OnStar® to identify the specific vehicle. Because these numbers are tied to the vehicle identification number of the vehicle, you must never exchange these parts with those of another vehicle. Replacement of the back-up battery (BUB) does not require reconfiguration of the VCIM. If a trouble code is indicated before the battery is replaced, the DTC must be cleared following the installation of the new battery. The OnStar® system does not need to be reconfigured unless the VCIM is replaced. When the VCIM is replaced, the OnStar® system must be reconfigured. Failure to reconfigure the system will result in an additional customer visit for repair. In addition, pressing and holding the white dot button on the keypad will NOT reset this version of the OnStar® system. This action will cause a DTC to set.

Communication Interface Module Battery Replacement

Scheme 17

Scheme 17: Wireless Communication Interface Antenna Replacement
Scheme 17: Wireless Communication Interface Antenna Replacement
CalloutComponent Name
1Wireless Communication Interface Antenna Assembly Procedure Access the antenna through the trunk by removing four push pins toward the rear of the vehicle that retain the upper fabric cover. Unsnap the antenna from the communication interface module.

Wireless Communication Interface Antenna Replacement

Scheme 18

Scheme 18: Communication Interface Module Bracket Replacement
Scheme 18: Communication Interface Module Bracket Replacement
CalloutComponent Name
Preliminary Procedure Remove the rear window panel trim. Refer to Rear Window Panel Trim Replacement (with DB3) , Rear Window Panel Trim Replacement (without DB3) , Rear Window Panel Trim Replacement (With HP6) .
1Communication Interface Module Bracket Fastener
2Communication Interface Module Bracket Procedure Disconnect the electrical connectors.

Communication Interface Module Bracket Replacement

Scheme 19

Scheme 19: Radio Replacement
Scheme 19: Radio Replacement
CalloutComponent Name
Preliminary Procedures Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection . Remove the instrument panel upper center trim panel. Refer to Instrument Panel Upper Center Trim Panel Replacement . NOTE: The Center of the Radio Assembly may have a mounted Bluetooth Antenna. Do not touch or apply any pressure to the Bluetooth Antenna during removal or installation.
1Radio Fastener (Qty: 4) CAUTION: Refer to Fastener Caution .
2Radio Procedure Disconnect the electrical connections. After repairs, refer to Control Module References for programming and set up information.
NOTE
The Center of the Radio Assembly may have a mounted Bluetooth Antenna. Do not touch or apply any pressure to the Bluetooth Antenna during removal or installation.
CAUTION
Refer to Fastener Caution .

Radio Replacement

Scheme 20

Scheme 20: Radio Control Assembly Replacement
Scheme 20: Radio Control Assembly Replacement
CalloutComponent Name
Procedure Remove the instrument panel upper center trim panel. Refer to Instrument Panel Upper Center Trim Panel Replacement
1Instrument Panel Accessory Bezel Fastener (Qty: 4)
2Instrument Panel Lower Trim Panel
3Radio Control Fastener (Qty: 7)
4Radio Control Assembly

Radio Control Assembly Replacement

Scheme 21

Scheme 21: Audio Disc Player and USB Receptacle Replacement
Scheme 21: Audio Disc Player and USB Receptacle Replacement
CalloutComponent Name
Preliminary Procedure Remove the front floor console compartment. Refer to Front Floor Console Compartment Replacement .
1Audio Disc Player and USB Receptacle Procedure Depress the tabs and remove the receptacle from the rear compartment. TIP: The rear compartment does not need to be removed from the front floor console cup holder housing to remove the receptacle.

Audio Disc Player and USB Receptacle Replacement

Scheme 22

Scheme 22: Radio Speaker Amplifier Replacement
Scheme 22: Radio Speaker Amplifier Replacement
CalloutComponent Name
Preliminary Procedure Remove the rear compartment side trim panel. Refer to Rear Compartment Side Trim Panel Replacement (without HP6) , Rear Compartment Side Trim Panel Replacement (HP6, Left Side) , Rear Compartment Side Trim Panel Replacement (HP6, Right Side) .
1Radio Speaker Amplifier Nut (Qty: 3) CAUTION: Refer to Fastener Caution .
2Radio Speaker Amplifier Bolt (Qty: 3)
3Radio Speaker Amplifier Assembly Procedure Disconnect the electrical connectors. For programming and set up information, refer to Control Module References .
CAUTION
Refer to Fastener Caution .

Radio Speaker Amplifier Replacement

Scheme 23

Scheme 23: Multimedia Player Interface Module Replacement
Scheme 23: Multimedia Player Interface Module Replacement
CalloutComponent Name
Preliminary Procedure Remove the instrument panel compartment. Refer to Instrument Panel Compartment Replacement .
1Multi Media Player Interface Module Assembly Procedure Disconnect the electrical connectors. Unsnap to release the module from the bracket.

Multimedia Player Interface Module Replacement

Scheme 24

Scheme 24: Navigation Signal Splitter Replacement
Scheme 24: Navigation Signal Splitter Replacement
CalloutComponent Name
Preliminary Procedure Remove the rear window panel trim. Refer to Rear Window Panel Trim Replacement (with DB3) , Rear Window Panel Trim Replacement (without DB3) , Rear Window Panel Trim Replacement (With HP6) .
1Navigation Signal Splitter Assembly Procedure Disconnect the electrical connectors. Unsnap the navigation signal splitter from the bracket.

Navigation Signal Splitter Replacement

Scheme 25

Scheme 25: Radio Antenna Coil Replacement - High Side
Scheme 25: Radio Antenna Coil Replacement - High Side
CalloutComponent Name
Preliminary Procedure Remove the left body lock pillar upper trim panel. Refer to Body Lock Pillar Upper Trim Panel Replacement .
1Radio Antenna Coil Fastener CAUTION: Refer to Fastener Caution . Tighten 9 N.m (80 lb in)
2Radio Antenna Coil Procedure Disconnect the electrical connectors.
CAUTION
Refer to Fastener Caution .

Radio Antenna Coil Replacement - High Side

Scheme 26

Scheme 26: Radio Antenna Coil Replacement - Ground Side
Scheme 26: Radio Antenna Coil Replacement - Ground Side
CalloutComponent Name
Preliminary Procedure Remove the right body lock pillar upper trim panel. Refer to Body Lock Pillar Upper Trim Panel Replacement .
1Radio Antenna Coil Fastener CAUTION: Refer to Fastener Caution . Tighten 8 N.m (71 lb in)
2Radio Antenna Coil Procedure Disconnect the electrical connector.
CAUTION
Refer to Fastener Caution .

Radio Antenna Coil Replacement - Ground Side

Scheme 27

Scheme 27: Radio Antenna Base Replacement
Scheme 27: Radio Antenna Base Replacement
CalloutComponent Name
Preliminary Procedure Lower the rear of the headlining trim panel. Refer to Headlining Trim Panel Replacement (with Sunroof) , Headlining Trim Panel Replacement (without Sunroof) .
1Radio Antenna Base Fastener
2Radio Antenna Base Retainer Procedure Use a new retainer.
3Radio Antenna Base Assembly Procedure Disconnect the electrical connector.

Radio Antenna Base Replacement

Scheme 28

Scheme 28: Radio Antenna Module Replacement
Scheme 28: Radio Antenna Module Replacement
CalloutComponent Name
Preliminary Procedure Remove the right body lock pillar upper trim panel. Refer to Body Lock Pillar Upper Trim Panel Replacement .
1Radio Antenna Module Fastener CAUTION: Refer to Fastener Caution . Tighten 9 N.m (80 lb in)
2Radio Antenna Module
CAUTION
Refer to Fastener Caution .

Radio Antenna Module Replacement

Scheme 29

Scheme 29: Radio and Telephone Control Switch Replacement
Scheme 29: Radio and Telephone Control Switch Replacement
CalloutComponent Name
Preliminary Procedure Remove the steering wheel lower cover. Refer to Steering Wheel Spoke Lower Cover Replacement .
1Steering Wheel Lower Cover Fastener (Qty: 2)
2Radio and Telephone Control Switch Assembly

Radio and Telephone Control Switch Replacement

Scheme 30

Scheme 30: Audio and Video Module Cable Replacement
Scheme 30: Audio and Video Module Cable Replacement
CalloutComponent Name
Preliminary Procedures Remove the radio. Refer to Radio Replacement . Remove the instrument panel compartment. Refer to Instrument Panel Compartment Replacement . Remove the front floor console. Refer to Front Floor Console Assembly Replacement .
1Audio and Video Module Cable Procedure Disconnect the electrical connectors at each end of the audio and video module cable. If the cable is taped into the wiring harness then cut the ends off the old cable and route the new cable as close to the old one as possible using tie straps to secure the new cable.

Audio and Video Module Cable Replacement

Scheme 31

Scheme 31: Digital Video Antenna Cable Replacement
Scheme 31: Digital Video Antenna Cable Replacement
CalloutComponent Name
Preliminary Procedures Remove the radio. Refer to Radio Replacement .
1Digital Video Antenna Cable Procedure Disconnect the electrical connectors at each end of the cable. If the antenna cable is taped into the wiring harness then cut the ends off the old cable and route the new cable as close to the old one as possible using tie straps to secure the new cable.

Digital Video Antenna Cable Replacement

Scheme 32

Scheme 32: Digital Radio Antenna Cable Replacement (Body Wiring Harness)
Scheme 32: Digital Radio Antenna Cable Replacement (Body Wiring Harness)
CalloutComponent Name
Preliminary Procedures Lower the headlining trim panel where needed. Refer to Headlining Trim Panel Replacement (with Sunroof) , Headlining Trim Panel Replacement (without Sunroof) . Remove the left body lock pillar upper trim panel. Refer to Body Lock Pillar Upper Trim Panel Replacement . Remove the left body lock pillar lower trim panel. Refer to Body Lock Pillar Lower Trim Panel Replacement . Remove the front or rear side door sill trim plate. Refer to Front and Rear Side Door Sill Trim Plate Replacement . Position the front floor panel carpet as needed. Refer to Front Floor Panel Carpet Replacement .
1Digital Radio Antenna Cable Procedure Disconnect the electrical connectors at each end of the antenna. If the antenna cable is taped into the wiring harness then cut the ends off the old antenna and route the new antenna as close to the old one as possible using tie straps to secure the new cable.

Digital Radio Antenna Cable Replacement (Body Wiring Harness)

Scheme 33

Scheme 33: Digital Radio Antenna Cable Replacement (Instrument Panel Wiring Harness)
Scheme 33: Digital Radio Antenna Cable Replacement (Instrument Panel Wiring Harness)
CalloutComponent Name
Preliminary Procedures Remove radio. Refer to Radio Replacement . Remove the instrument panel lower trim panel reinforcement. Refer to Instrument Panel Lower Trim Panel Reinforcement Replacement . Position the front floor panel carpet as needed. Refer to Front Floor Panel Carpet Replacement .
1Digital Radio Antenna Cable Procedure Disconnect the electrical connectors at each end of the cable. If the antenna cable is taped into the wiring harness then cut the ends off the old cable and route the new cable as close to the old one as possible using tie straps to secure the new cable.

Digital Radio Antenna Cable Replacement (Instrument Panel Wiring Harness)

Scheme 34

Scheme 34: Radio Antenna Cable Replacement
Scheme 34: Radio Antenna Cable Replacement
CalloutComponent Name
Preliminary Procedures Remove the radio. Refer to Radio Replacement . Remove the instrument panel compartment. Refer to Instrument Panel Compartment Replacement .
1Radio Antenna Cable Procedure Disconnect the electrical connectors at each end of the antenna. If the antenna cable is taped into the wiring harness then cut the ends off the old antenna and route the new antenna as close to the old one as possible using tie straps to secure the new cable.

Radio Antenna Cable Replacement

Scheme 35

Scheme 35: Digital Radio Antenna and Navigation Antenna Coaxial Cable Replacement (Body Wiring Harness)
Scheme 35: Digital Radio Antenna and Navigation Antenna Coaxial Cable Replacement (Body Wiring Harness)
CalloutComponent Name
Preliminary Procedures Lower the headlining trim panel where needed. Refer to Headlining Trim Panel Replacement (with Sunroof) , Headlining Trim Panel Replacement (without Sunroof) . Remove the left body lock pillar upper trim panel. Refer to Body Lock Pillar Upper Trim Panel Replacement . Remove the left body lock pillar lower trim panel. Refer to Body Lock Pillar Lower Trim Panel Replacement . Remove the front or rear side door sill trim plate. Refer to Front and Rear Side Door Sill Trim Plate Replacement . Position the front floor panel carpet as needed. Refer to Front Floor Panel Carpet Replacement . Remove the rear window panel trim. Refer to Rear Window Panel Trim Replacement (with DB3) , Rear Window Panel Trim Replacement (without DB3) , Rear Window Panel Trim Replacement (With HP6) .
1Digital Radio Antenna and Navigation Antenna Coaxial Cable Procedure Disconnect the electrical connectors at each end of the cable. If the antenna cable is taped into the wiring harness then cut the ends off the old cable and route the new cable as close to the old one as possible using tie straps to secure the new cable.

Digital Radio Antenna and Navigation Antenna Coaxial Cable Replacement (Body Wiring Harness)

Scheme 36

Scheme 36: Digital Radio Antenna and Navigation Antenna Coaxial Cable Replacement (Instrument Panel Wiring Harn
Scheme 36: Digital Radio Antenna and Navigation Antenna Coaxial Cable Replacement (Instrument Panel Wiring Harn
CalloutComponent Name
Preliminary Procedures Remove radio. Refer to Radio Replacement . Remove the instrument panel lower trim panel reinforcement. Refer to Instrument Panel Lower Trim Panel Reinforcement Replacement . Position the front floor panel carpet as needed. Refer to Front Floor Panel Carpet Replacement .
1Digital Radio Antenna and Navigation Antenna Coaxial Cable Procedure Disconnect the electrical connectors at each end of the cable. If the antenna cable is taped into the wiring harness then cut the ends off the old cable and route the new cable as close to the old one as possible using tie straps to secure the new cable.

Digital Radio Antenna and Navigation Antenna Coaxial Cable Replacement (Instrument Panel Wiring Harness)

Scheme 37

Scheme 37: Mobile Telephone And Navigation Antenna Coaxial Cable Replacement
Scheme 37: Mobile Telephone And Navigation Antenna Coaxial Cable Replacement
CalloutComponent Name
Preliminary Procedures Lower the headlining trim panel where needed. Refer to Headlining Trim Panel Replacement (with Sunroof) , Headlining Trim Panel Replacement (without Sunroof) . Remove the left body lock pillar upper trim panel. Refer to Body Lock Pillar Upper Trim Panel Replacement . Remove the rear window panel trim. Refer to Rear Window Panel Trim Replacement (with DB3) , Rear Window Panel Trim Replacement (without DB3) , Rear Window Panel Trim Replacement (With HP6) .
1Mobile Telephone and Navigation Antenna Coaxial Cable Procedure Disconnect the electrical connectors at each end of the antenna. If the antenna cable is taped into the wiring harness then cut the ends off the old antenna and route the new antenna as close to the old one as possible using tie straps to secure the new cable.

Mobile Telephone and Navigation Antenna Coaxial Cable Replacement

Scheme 38

Scheme 38: Video Display Replacement
Scheme 38: Video Display Replacement
CalloutComponent Name
1Video Display Fastener (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten 9.5 N.m (84 lb in)
2Video Display Assembly Procedure Disconnect the electrical connections.
CAUTION
Refer to Fastener Caution .

Video Display Replacement

Scheme 39

Scheme 39: Audio/Video Disc Player Adapter Replacement
Scheme 39: Audio/Video Disc Player Adapter Replacement
CalloutComponent Name
Preliminary Procedure Remove the front floor console rear cover. Refer to Front Floor Console Rear Cover Replacement .
1Audio/Video Disc Player Adapter Assembly Procedure Depress the four tabs and remove the adapter from the rear cover.

Audio/Video Disc Player Adapter Replacement

Scheme 40

Scheme 40: Radio Front Speaker Grille Replacement
Scheme 40: Radio Front Speaker Grille Replacement
CalloutComponent Name
1Radio Front Speaker Grille Assembly Procedure Use a flat-bladed plastic trim tool to aid in the removal of the speaker grille. Disconnect the electrical connector. When replacing the speaker grille, transfer all necessary components.

Radio Front Speaker Grille Replacement

Scheme 41

Scheme 41: Radio Front Speaker Replacement
Scheme 41: Radio Front Speaker Replacement
CalloutComponent Name
Preliminary Procedure Remove the radio front speaker grille. Refer to Radio Front Speaker Grille Replacement .
1Radio Front Center Speaker Fastener (Qty: 2)
2Radio Front Speaker Procedure Disconnect the electrical connector.

Radio Front Speaker Replacement

Scheme 42

Scheme 42: Radio Windshield Side Garnish Molding Speaker Replacement
Scheme 42: Radio Windshield Side Garnish Molding Speaker Replacement
CalloutComponent Name
Preliminary Procedure Remove the windshield side garnish molding. Refer to Windshield Side Garnish Molding Replacement .
1Radio Windshield Side Garnish Molding Speaker Procedure Unsnap to release the speaker from the garnish molding.

Radio Windshield Side Garnish Molding Speaker Replacement

Scheme 43

Scheme 43: Radio Front Side Door Speaker Replacement
Scheme 43: Radio Front Side Door Speaker Replacement
CalloutComponent Name
Preliminary Procedure Remove the front side door trim panel. Refer to Front Side Door Trim Panel Replacement .
1Radio Front Side Door Speaker Fastener
2Radio Front Side Door Speaker Procedure Disconnect the electrical connector.

Radio Front Side Door Speaker Replacement

Scheme 44

Scheme 44: Radio Rear Speaker Replacement
Scheme 44: Radio Rear Speaker Replacement
CalloutComponent Name
Preliminary Procedure Remove the rear window panel trim. Refer to Rear Window Panel Trim Replacement (with DB3) , Rear Window Panel Trim Replacement (without DB3) , Rear Window Panel Trim Replacement (With HP6) .
1Radio Rear Speaker Fastener (Qty: 4)
2Radio Rear Speaker (Qty: 4) Procedure Disconnect the electrical connectors.

Radio Rear Speaker Replacement

Scheme 45

Scheme 45: Radio Rear Side Door Speaker Replacement
Scheme 45: Radio Rear Side Door Speaker Replacement
CalloutComponent Name
Preliminary Procedure Remove the rear side door trim panel. Refer to Rear Side Door Trim Panel Replacement .
1Radio Rear Side Door Speaker Fastener
2Radio Rear Side Door Speaker Procedure Disconnect the electrical connector.

Radio Rear Side Door Speaker Replacement

OnStar Description and Operation

This OnStar® system consists of the following components

  1. Telematics communication interface control module
  2. OnStar® three button assembly
  3. Microphone
  4. Cellular antenna
  5. Navigation antenna
  6. Bluetooth® antenna (If equipped)
  7. Back up battery (If equipped)

This system also interfaces with the factory installed vehicle audio system.

Telematics Communication Interface Control Module

The telematics communication interface control module is a cellular device that allows the user to communicate data and voice signals over the national cellular network. Power is provided by a dedicated, fused B+ circuit. Ground is provided through the vehicle wiring harness attached to the module. The ignition state is determined by the telematics communication interface control module through serial data messaging.

Dedicated circuits are used to connect the telematics communication interface control module to a microphone, the button assembly, and to command the status LED. The telematics communication interface control module communicates with the rest of the vehicle over the serial data bus.

The module houses 2 technology systems, one to process GPS data, and another for cellular information. The cellular system connects the OnStar® system to the cellular carrier's communication system by interacting with the national cellular infrastructure. The module sends and receives all cellular communications over the cellular antenna and cellular antenna coax. GPS satellites orbiting earth are constantly transmitting signals of their current location. The OnStar® system uses the GPS signals to provide location on demand.

The module also has the capability of activating the horn, initiating door lock/unlock, or activating the exterior lamps using the serial data circuits. These functions can be commanded by the OnStar® Call Center per a customer request.

OnStar® Three Button Assembly

The OnStar® button assembly may be part of the rearview mirror, or a separate, stand alone unit. The button assembly is comprised of 3 buttons and a status LED. The buttons are defined as follows

  1. The answer/end call button, which is black with a white phone icon, allows the user to answer and end calls or initiate speech recognition.
  2. The blue OnStar® call center button, which displays the OnStar® logo, allows the user to connect to the OnStar® call center.
  3. The emergency button, which displays a white cross with a red background, sends a high priority emergency call to the OnStar® call center when pressed.

The telematics communication interface control module supplies 10 volts to the OnStar® button assembly on the keypad supply voltage circuit. When pressed, each button completes a circuit across a resistor allowing a specific voltage to be returned to the telematics communication interface control module on the keypad signal circuit. Depending upon the voltage range returned the telematics communication interface control module is able to identify which button has been pressed.

The OnStar® status LED is located with the button assembly. The LED is green when the system is ON and operating normally. When the status LED is green and flashing, it is an indication that a call is in progress. When the LED is red, this indicates a system malfunction is present. In the event there is a system malfunction and the OnStar® system is still able to make a call, the LED will flash red during the call.

If the LED does not illuminate, this may indicate that the customers OnStar® subscription is not active or has expired. Push the blue OnStar button to connect to an advisor who can then verify the account status.

Each LED is controlled by the telematics communication interface control module over dedicated LED signal circuits. Ground for the LED is provided by the wiring harness attached to the button assembly.

Secondary OnStar® Controls

Some vehicles may have an additional button that when pushed can engage the OnStar® system. The button may be a symbol of a face with sound waves, or may say MUTE, or be a symbol of a radio speaker with a slash through it.

By engaging the OnStar® system with this feature, the user can interact with the system by use of voice commands. A complete list of these commands is supplied in the information provided to the customer. If the information is not available for reference, at any command prompt the user can say "HELP" and the telematics communication interface control module will return an audible list of available commands.

OnStar® Microphone

The OnStar®, or cellular microphone, can be a part of the rearview mirror assembly, or on some vehicle lines, a separate, stand alone unit. In either case, the telematics communication interface control module supplies approximately 10 volts to the microphone on the cellular microphone signal circuit, and voice data from the user is sent back to the telematics communication interface control module over the same circuit. A cellular microphone low reference circuit or a drain wire provides a ground for the microphone.

Cellular and GPS Antennas

This vehicle will be equipped with one of the following types of antennas

  1. A combination cellular and navigation antenna, which brings the functions of both into a single part
  2. A cellular, GPS, and digital radio receiver antenna, which also incorporates the functionality of the digital radio receiver satellite antenna (XM).
  3. A cellular, GPS, and digital radio receiver antenna, which also incorporates the AM/FM antenna.

The cellular antenna is the component that allows the OnStar® system to send and receive data over airwaves by means of cellular technology. The antenna is connected at the base to a coax cable that plugs directly into the telematics communication interface control module.

The GPS antenna is used to collect the signals of the orbiting GPS satellites. Within the antenna is housed a low noise amplifier that allows for a more broad and precise reception of this data. The antenna is connected at the base to a coax cable that plugs directly into the telematics communication interface control module. The cable also provides a path for DC current for powering the antenna.

The OnStar® Call Center also has the capability of communicating with the vehicle during an OnStar® call to retrieve the latest GPS location and transmit it to the OnStar® Call Center. A history location of the last recorded position of the vehicle is stored in the module and marked as aged, for as long as the module power is not removed. Actual GPS location may take up to 10 minutes to register in the event of a loss of power.

OnStar® RemoteLink

OnStar® RemoteLink is a mobile app to link mobile devices to a vehicle for limited diagnostics and feature controls. After downloading the app and registering the device, vehicle owners with an eligible vehicle can use their mobile devices to access real-time data from their vehicle and perform specific commands remotely.

All communication between the app and the vehicle is powered by OnStar's® advanced connected vehicle technology. An active OnStar® account as well as a valid OnStar® username and password are required to use the app. The remote commands must be enabled by logging into the user's OnStar® account prior to using the app.

Vehicle Control Features

  1. Lock/Unlock doors
  2. Start vehicle remotely
  3. Activate your Horn & Lights
  4. Contact an OnStar Advisor, Roadside Assistance or your Preferred Dealer

Available Vehicle Data

  1. Real-time fuel information, including fuel range, fuel remaining, and lifetime MPG
  2. Lifetime mileage
  3. Remaining oil life
  4. Current tire pressure information
  5. OnStar® account information

Compass Heading

The telematics communication interface module has a compass feature to calculate vehicle direction which is displayed via the instrument panel cluster or designated display. The compass heading is determined by dead reckoning until the GPS 3d fix is established. The dead reckoning is accomplished by using the yaw rate sensors and wheel ticks to determine heading changes from a GPS known heading. The GPS 3d fix heading is determined by the deferential of two locations.

Bluetooth® (If Equipped)

Bluetooth® wireless technology is a short-range communications technology intended to replace the cables connecting portable and/or fixed devices while maintaining high levels of security. Only vehicles with steering wheel controls will have Bluetooth® functionality. In order to utilize the vehicle's Bluetooth® system, a Bluetooth® equipped cellular phone is required.

The Bluetooth® antenna is a small fixed antenna connected directly to the telematics communication interface control module and is used to send and receive signals from a Bluetooth® enabled cellular phone. The antenna utilizes no cabling and is not external to the vehicle. The available features and functions are determined by the software within the device being used and the telematics communication interface control module. The operating range of the signal from the vehicle is approximately 30 feet. Note that the operating range is dependent upon the cellular phone being used and battery level of the phone.

With Bluetooth® technology customers can experience hands-free calling as their Bluetooth® capable cellular phones are wirelessly connected to the vehicle. It will allow customers to place and receive calls using the steering wheel controls and voice recognition. The vehicle audio system will allow you to listen to your call through the vehicle speakers and adjust volume through steering wheel or radio controls.

Not all Bluetooth® cellular phones are guaranteed to work with the vehicle's Bluetooth® system. Based on the cellular phone's service provider and the manufacturer's implementation of Bluetooth®, not all phones support all available Bluetooth® functionality. Bluetooth® enabled cellular phones will be tested for vehicle compatibility and a feature compatibility list will be provided via the GM Bluetooth® website: http://www.gm.com/vc/bluetooth/

Bluetooth® Features Supported

The following is a list of features supported by the Bluetooth® system. Note that not all devices will support all of the listed functions.

  1. Automatic reconnection - highest priority phone will automatically be connected to vehicle when vehicle ignition is on
  2. Hands-free dialing- via digits, redial, name tags (phone number saved to a nametag via voice recognition)
  3. Answering a call
  4. Ending a call
  5. Mute a Call
  6. Rejecting a call - ignore an incoming call
  7. Call Waiting
  8. Three-way Calling - initiated from hands-free system
  9. Send Number During a Call - this is used when calling a menu-driven phone system
  10. Transfer a Call - transfer call from vehicle to cellular phone and visa versa
  11. Voice Pass-Thru - allow access to the voice recognition commands on the cellular phone

Pairing a Bluetooth® Cellular Phone to the Vehicle

In order to use hands-free calling, the cellular phone must be paired to the vehicle. Up to five devices can be paired to the vehicle at one time, but only one can be connected at any given time. To pair a phone, the customer must know how to operate the Bluetooth® functionality of their phone. The pairing process must only be done one time for each phone, unless that phone's information is deleted. For safety reasons, the pairing process is disabled while the vehicle is moving.

Once the Bluetooth® cellular phone has been paired with vehicle, it will automatically connect to the vehicle when the ignition is on and the device is on. When more than one paired phone is in the vehicle, the phone with the highest priority will be connected. If the cellular phone is in use while getting into the vehicle, the phone can be switched to hands-free mode with the press of a button. In addition, a call in progress can be transferred from the vehicle hands-free mode to the phone to continue the call as the customer exits the vehicle.

Complete pairing instructions are provided in the Vehicle Owners Manual.

Back-up Battery (If Equipped)

IMPORTANTDo not disconnect the main vehicle battery or remove the OnStar® fuse with the ignition key in any position other than OFF. Disconnecting power to the OnStar® module in any way while the ignition is ON or with retained accessory power activated may cause activation of the OnStar® Back-Up Battery. This action is per design as the back-up battery is designed to provide power to the telematics communication interface control module so an emergency notification call can be made after an event where the main battery is disabled. Once the Back-Up Battery is activated it will stay on until the power is restored back to the telematics communication interface control module. The telematics communication interface control module naturally chooses the main supply voltage as it's default supply, but if the main supply is removed or lost for any reason the OnStar® module will use the Back-Up Battery as a power supply as long as the default supply can not be detected. The back-up battery is not rechargeable and once discharged below 9.5 volts the back-up battery must be replaced.

Certain OnStar® equipped vehicles may also be equipped with a back-up battery. The back-up battery is a non-rechargeable, lithium battery intended to provide an auxiliary power source for the telematics communication interface control module in the event where power from the main vehicle battery is lost.

The back-up battery is intended to have a limited life span of approximately 4 years and is designed to maintain an open circuit voltage between 16 V and 9 V throughout this period. This allows the battery to power the basic functions of the telematics communication interface control module for least one 200 second (5 minute) call at the end of the 4 year span, should the main vehicle battery be lost. In the case of a vehicle losing vehicle battery power, OnStar will switch over to the backup battery based on an internal algorithm. It will look for an air-bag deploy, or near-deploy, messages from the SDM. If there are no messages the OnStar module will stay wake for a few minutes longer and monitor the buttons in the mirror. If not pressed, the modules will power down and shut off completely.

The back-up battery is connected to the telematics communication interface control module through the back-up battery positive voltage circuit and back-up battery ground circuit and is protected from a short circuit by means of an internal fuse. In the event the back-up battery, battery positive voltage circuit is shorted to the back-up battery ground circuit or chassis ground, the fuse will open and render the back-up battery permanently inoperable. The status of the back-up battery and its associated wiring is monitored by the telematics communication interface control module.

Audio System Interface

When the OnStar® requires audio output, a serial data message is sent to the audio system to mute all radio functions and transmit OnStar® originated audio. The OnStar® audio is transmitted to the vehicle audio system by a dedicated signal circuit and a low reference circuit.

The audio system will mute and an audible ring will be heard though the speakers if the vehicle receives a call with the radio ON.

On some vehicles, the HVAC blower speed may be reduced when the OnStar® system is active to aid in reducing interior noise. When the system is no longer active, the blower speed will return to its previous setting.

OnStar® Sleep Cycle

The OnStar® system uses a unique sleep cycle to allow the system to receive cellular calls while the ignition is in the OFF position and retained accessory power mode has ended. This cycle enables the telematics communication interface control module to perform remote functions, such as door unlock, as commanded over the air by the OnStar® Call Center, and to continue to maintain an acceptable level of battery electrical drain.

The OnStar® system uses 4 states of readiness, depending upon the type of cellular market the vehicle is in when the ignition is put into the OFF state

  1. High power
  2. Low power
  3. Sleep
  4. Digital standby

The high power state is in effect whenever the ignition is in the ON or RUN position, or retained accessory power is enabled, and the OnStar® system is sending or receiving calls or when the system is performing a remote function.

The low power state is in effect when the OnStar® system is idle with the ignition in the ON or RUN position, or with retained accessory power enabled.

The sleep state is entered after the vehicle has been shut off and the retained accessory power has timed out while in an analog cellular area. At a predetermined time recorded within the telematics communication interface control module, the system re-enters the low power state to listen for a call from the OnStar® Call Center for 1 minute. After this interval, the system will again return to the sleep state for 9 minutes. If a call is sent during the 1 minute interval, the OnStar® system will receive the call and immediately go into the high power mode to perform any requested functions. If no call is received during the 1 minute interval, the system will go back into the sleep mode for another 9 minutes. This process will continue for up to 48 hours, after which the OnStar® system will turn off until the ignition is turned to the ON or RUN position.

The digital standby power state is entered after the vehicle has been shut off and the retained accessory power has timed out while in a digital cellular area. When in digital standby mode, the OnStar® module is able to perform all remote functions as commanded by an OnStar® advisor at any time, for a continuous 120 hours. After 120 hours, the OnStar® module will go into sleep mode until a wake up signal from the vehicle is seen by the telematics communication interface control module. If the OnStar module loses the digital cellular signal it will revert to analog mode and follow the standard sleep state (9 minutes OFF, 1 minute standby) based on the time of the GPS signals, this will continue until a digital cellular signal is again received.

If the OnStar® system loses battery power while the system is in a standby or sleep mode, the system will remain OFF until battery power is restored and the ignition is turned to the ON or RUN position.

Features

OnStar® Personal Calling

The hands free, OnStar® personal calling cellular phone feature is an additional feature of the OnStar® system. This feature is embedded within the telematics communication interface control module; however it must be activated by an OnStar® advisor. OnStar® personal calling operates similar to most hand held cellular phones in that the availability for its usage is based on minutes or units. The customer must have a current OnStar® subscription, as this feature cannot be utilized without it. To use OnStar® personal calling, the customer must also purchase units (minutes) as outlined in the owners guide provided with the OnStar® system. Units begin to deplete, 1 unit is equal to 1 minute, as the customer makes outbound phone calls, answers inbound phone calls, or while connected to the OnStar® virtual advisor. In addition, units may also have an expiration date, depending upon the type of units purchased.

Customers have the ability to store telephone numbers within the module, referenced by a nametag for the convenience of frequently dialed numbers. After storing a nametag, the user can dial this number by initiating the OnStar® personal calling feature, speaking the word "call," and repeating the nametag assigned.

Turn by Turn Navigation

Turn by Turn Navigation allows the driver to contact OnStar® to obtain directions for driving from a current location to a desired location. The Turn by Turn Navigation system stores your planned route and continually checks your position along that route, when you deviate from the planned route, the system will recognize this and prompt the driver with verbal prompts for how to proceed. The driver then responds verbally to direct the system to continue the current routing or to recalculate the route because of a missed turn.

Advisor Record Feature

The Advisor Record Feature allows the user to store any information given during a call with an OnStar® Advisor. Recording is activated by pressing the blue OnStar button during a call; pressing the button a second time stops the recording. The stored information can be played back by pressing the phone button on the three button assembly and using the voice command "Advisor Playback".

Deactivated OnStar® Accounts

In the event a customer has not renewed their OnStar® account after expiration or the account was never activated, OnStar® will make a discrete cellular call to the vehicle to deactivate the OnStar® system. Before taking this action, customers are notified that the OnStar® system in their vehicle will be deactivated unless they elect to renew the account. After the OnStar® account has been deactivated, customers will experience the following

  1. The OnStar® status LED will not illuminate.
  2. The OnStar® system will NOT attempt to connect to the OnStar® Call Center in the event of a collision or if the vehicle's front air bags deploy for any other reason.
  3. An emergency button press will play a demo message indicating the service has been deactivated.
  4. An OnStar® Call Center button press will connect the customer with a dedicated sales team who can sell an OnStar® subscription and reactivate the vehicle. Depending on the type of OnStar® hardware in the vehicle, the customer may first hear a demonstration message stating there is no current OnStar® subscription for the vehicle, and directing the customer what to do to activate services.
  5. OnStar® personal calling will not be available, as this feature requires the customer to have a current OnStar® account. Attempts to use this feature may result in cellular connection failure messages and the inability to connect to the number dialed.

Certain vehicles that have never had an active OnStar® account, or that have been deactivated, may be unable to establish a connection with the OnStar® Call Center. When normal published diagnostic procedures do not indicate a possible cause for the no connect concern, the vehicle may have been deactivated. For deactivated vehicles, a no connect response should be considered normal operation. Further diagnosis and subsequent repair is only necessary should the customer elect to become an active OnStar® subscriber or renew the account subscription.

OnStar® Cellular, GPS, and Diagnostic Limitations

The proper operation of the OnStar® System is dependent on several elements outside the components integrated into the vehicle. These include the National Cellular Network Infrastructure, the cellular telephone carriers within the network, and the GPS.

The cellular operation of the OnStar® system may be inhibited by factors such as the users range from an analog or digital cellular tower, the state of the cellular carrier's equipment, and the location where the call is placed. Making an OnStar® key press in areas that lack sufficient cellular coverage or have a temporary equipment failure will result in either the inability of a call to complete with a data transfer or the complete inability to connect to the OnStar® Call Center. The OnStar® system may also experience connection issues if the identification numbers for the module, station identification number, electronic serial number or manufacturers electronic ID, are not recognized by the cellular carriers local signal receiving towers.

The satellites that orbit earth providing the OnStar system with GPS data have almost no failures associated with them. In the event of a no GPS concern, the failure will likely lie with the inability of the system to gain GPS signals because of its location, i.e. in a parking structure, hardware failure, or being mistaken with an OnStar® call which has reached the Call Center without vehicle data.

During diagnostic testing of the OnStar® system, the technician should ensure the vehicle is located in an area that has a clear unobstructed view of the open sky, and preferably, an area where analog or digital cellular calls have been successfully placed. These areas can be found by successfully making an OnStar® keypress in a known good OnStar® equipped vehicle and confirming success with the OnStar® Call Center advisor. Such places can be used as a permanent reference for future OnStar® testing.

Mobile Identification Number and Mobile Directory Number

The telematics communication interface control module utilizes 2 numbers for cellular device identification, call routing and connection, a mobile identification number and a mobile directory number. The mobile identification number represents the number used by the cellular carrier for call routing purposes while the mobile directory number represents the number dialed to reach the cellular device.

Operation of the OnStar® Speech Recognition Systems

OnStar® users communicate with 2 speech recognition systems. Speech recognition allows the user to speak to one computer in the vehicle, and one reached over a phone line. The computer tries to understand the users command, and responds by speaking back, or by taking the appropriate action, e.g. dialing the phone.

  1. Personal Calling uses a speech recognition system that resides in the vehicle. When the user presses the phone button, the system states, Ready, and listens for the user's command. The user can speak commands to control the hands-free phone.
  2. Virtual advisor is a remote speech recognition system that the caller can access by making a phone call. The user connects to virtual advisor by requesting it during personal calling use. The user is then transferred to the virtual advisor server and talks to it via a cellular connection.

The OnStar® speech recognition systems use speech technology that is designed to understand a wide range of American English speakers. Although there is no one right way to speak English, the system will work best when users try to modify their pronunciation should they encounter difficulty. Users who do not obtain good results are advised to try the tips and workarounds found in this section.

ConcernTip for Better Result
NoiseNoise may confuse the speech recognition system. You usually get better performance from the system in quieter conditions: The HVAC fan creates noise. Turn it down or OFF for better speech system performance. Driving at high speeds creates louder engine noise and wind noise. You may get better results at lower speeds. An open window or an open sunroof allows more noise to enter the vehicle. Close all windows for better results. Noisy rainstorms can also reduce performance. If passengers are talking while you use the speech system, it may be confused by their speech. You will get better results if all occupants of the vehicle are quiet while the system is listening for commands.
When to SpeakIn Personal Calling, the system is only listening after it prompts you to speak with a beep. When the system prompts you to speak, you have about 5 seconds to respond. If the system does not hear a response, it will prompt you again, or cancel the transaction. If you begin to speak too soon, try pausing for a half second before speaking after the beep. In the Virtual Advisor, the system is always listening for commands, even while it is speaking.
How to SpeakSpeak forcefully, and clearly. The noisier the environment, the louder you need to speak. If you are in the driver seat, speak facing the front of the car. If you are a passenger, speak facing the rearview mirror. Speak calmly, and naturally. The system may sometimes fail your repeated attempts to give a command. If your speech is distorted by shouting or frustration, this may cause more errors. People with high-pitched voices may have better results by speaking in a deeper, lower-pitched voice. However, do not lower the volume of the voice. Avoid speaking with a rising intonation, like asking a question. Use a flat or falling intonation, like giving an answer.
What to SayPersonal Calling: One-word commands The Personal Calling system listens for only one word at a time. There are some exceptions, 2-word phrases that are spoken and understood as a single word, e.g. "virtual advisor", "voice feedback", and "my number". You can enter phone numbers only one digit at a time, and the system repeats each digit as it hears it. Say "Help" at the Ready prompt to hear the list of Personal Calling commands. Virtual Advisor can understand sentences with more than one word. It also expects to hear a 4-digit number all at once when it asks for your PIN. Say, "What are my choices?" to hear a list of commands that the Virtual Advisor understands.
Entering a phone numberIf you have trouble getting numbers correctly into the system, store your frequently-called number in the directory, so the system will remember them. After you have stored a number with a nametag, then you simply say "call" and the nametag in order to call the number. If the system cannot understand your numbers, ask another person to help you enter your frequently-called numbers. This person can speak the numbers, then you can speak the nametag.
Storing or dialing a numberWhen you have finished speaking your phone number, you do not need to say "store" or "dial" to indicate that you are done. If you pause and say nothing, the system will ask you if you want to store or dial. Say "yes".
Creating nametagsShort nametags that are similar may be easily confused by the system. You may get better recognition of your nametags if you make them longer, for example "George Washington" without pause, instead of "George" only. If you want to use nametags while driving, it is best to store the nametag with some vehicle noise in the background. If you are in park while you are storing nametags, you can turn the fan on low or open windows in order to create some background noise.
Virtual Advisor 4-digit PINSay the 4 digits in a natural way, without pausing between digits.
InterruptingWhen the Virtual Advisor is speaking, you can interrupt it with another command. The first word in your command helps to get its attention. If the Virtual Advisor has trouble understanding your commands when you interrupt, try speaking the first word loudly and clearly, then pause for an instant, then continue with the rest of the command. For example: "Get... my weather" or "Lookup... a quote for General Motors".

General Tips for Better Speech Recognition

Radio/Audio System Description and Operation

The entertainment system on this vehicle may have several different configurations available to it. To determine the specific configuration of the vehicle, please see the Service Parts ID Label, and refer to RPO Code List .

Each item in the list below represents topics covered in detail below.

  1. Radio Circuit Operation
  2. Information Display and Controls
  3. Antenna System
  4. Radio Reception
  5. Speaker Operation
  6. Audio Amplifier (If equipped)
  7. Theft Deterrent
  8. Bluetooth ® (UP9) (if equipped)
  9. Applications (if equipped)
  10. Auxiliary Audio Input Jack (If equipped)
  11. USB Port (If equipped)
  12. Multimedia Player Interface Module (If equipped)
  13. Navigation System Components and Features (if equipped)
  14. OnStar ®
  15. Steering Wheel Controls (If equipped)
  16. Auto Volume Control

Radio Circuit Operation

Radio Power

The radio does not use a discrete ignition feed circuit for power moding. The power mode master provides the system power mode to the radio via serial data messages. The power mode master determines the system power mode by processing power mode information from ignition switch inputs. Serial data power modes supported by the radio are OFF, ACCESSORY, RUN, and CRANK REQUEST.

Radio Grounds

The vehicle harness provides a ground for the radio circuits. The radio may also be case grounded.

Radio Data Link Communication

The radio communicates with other modules via serial data.

Radio Audio Outputs

Each of the audio output channel circuits (+) and (-), at the radio have a DC bias voltage that is approximately one half of battery voltage. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound. The frequency (Hz) of the AC voltage signal is directly related to the frequency of the input (audio source playing) to the audio system. Both the DC bias voltage and the AC voltage signals are needed for the audio system to properly produce sound.

Remote Enable Output

The remote enable circuit is a discrete 12 V signal supplied to infotainment system components when the radio is producing audio, needs the front display on, needs video entertainment system components on, or needs to produce chimes. This signal is used to control the power state of the components. There is no output on radio the remote enable circuit when the vehicle is in the CRANK powermode, this is to minimize current consumption from the attached modules and also to avoid audio pops during crank events.

Scheme 46

Scheme 46: Information Display and Controls
Scheme 46: Information Display and Controls
CalloutComponent Name
1Radio/HVAC Controls
2Info Display Module
3Radio
4HVAC Control Module
5Data Link Connector
AGMLAN
BLocal Interconnect Network
CCAN Graphical Interface
DDigital Video
ETouch Screen Serial Data

The info display module has continuous power and ground. When the radio is on, a discrete 12 V signal is supplied on the remote enable circuit to the color display module. This signal is used to control the power state of the module, which is active when the signal is high and inactive when the signal is low.

The info display module receives digital video data from the radio for on-screen display information through the video signal circuits. The radio communicates with the info display module over the touch screen serial data circuits for touch screen inputs and backlighting dimming level.

The radio/HVAC controls communicate radio control inputs directly to the radio through the CAN Graphical Interface (CGI) data circuits. After receiving the message the radio will perform the requested function. Messages communicated between the radio and the radio/HVAC controls include the following

  1. Button presses/knob rotations
  2. Commands for the state of indicators
  3. Radio control back-lighting

HVAC data for controls and status indicators is communicated between the radio/HVAC controls and the HVAC control module with a separate LIN serial data circuit. HVAC status screen information from the HVAC control module is transmitted to the radio on the GMLAN serial data circuit. The radio then displays the desired screen information on the info display using the video data circuits.

Antenna System

Multi-Band Antenna

The multi-band antenna is located on the roof of the vehicle. This type of antenna may be used with the AM/FM radio, but is primarily for cellular and GPS signals and the XM™ Satellite Radio Service System, if the vehicle has these features. Keep this antenna clear of snow and ice build up for clear reception. If the vehicle has a sunroof, the performance of the system may be affected if the sunroof is open. Loading items onto the roof of the vehicle can interfere with the performance of the system, ensure the multi-band antenna is not obstructed.

Active Antenna

The active antenna system uses two integral antennas applied as appliqu e s to the rear glass. Each antenna is part of the rear window and looks similar to the defogger grid. One antenna receives AM signals while the other antenna receives FM signals. Any damage to the antenna requires replacing the glass.

The radio antenna module is enabled when the radio is turned on. The radio provides battery voltage to the antenna module using the center conductor of the antenna coaxial cable. This DC voltage does not affect the incoming radio signal. When a 12 V signal is seen by the module on the center conductor of the antenna coax, both AM and FM signals are amplified.

Radio Reception

AM/FM Radio Signal

The radio signal is sent from a broadcast station and is then received by an antenna. The strength of the signal received depends on the following

  1. The power output (wattage) of the broadcasting station
  2. The location of the vehicle (or receiver) relative to the broadcast tower.
  3. Height of the broadcast antenna
  4. Height of the receiving antenna
  5. Obstacles between the tower and the receiver
  6. Atmospheric conditions
  7. What band (AM or FM) the station is broadcasting
  8. Type of antenna and the ground plane

Digital Radio Receiver (If equipped)

The XM satellite receiver is integrated into the radio. XM satellite radio provides digital radio reception. The XM signal is broadcast from two satellites and, where necessary, terrestrial repeaters. The high power satellites allow the antenna to receive the XM signal even when foliage and other partial obstructions block the antennas view of the satellite. Terrestrial repeaters are used in dense urban areas. These repeaters will receive the satellite signal and re-broadcast them at much higher power levels in order to ensure reception in areas with densely packed tall buildings. A service fee is required in order to receive the XM service.

Radio Data System (RDS)

The RDS feature is available only on FM stations that broadcast RDS information. This system relies upon receiving specific information from these stations and only works when the information is available. While the radio is tuned to an FM-RDS station, the station name or call letters display. RDS data is carried in what is known as a "subcarrier". A subcarrier is a frequency that the FM broadcaster is authorized to use to send data that is not audible in the main audio program.

RDS functions will only work with FM broadcast stations that are broadcasting RDS data. Not all FM Broadcast stations broadcast RDS data or offer all of the RDS services.

The information displayed is dependent upon the information broadcast by the particular station. The information may vary greatly between stations. RDS functions may not work properly when reception is weak, reception is of poor quality, or RDS is not implemented properly by the FM Broadcaster. In some cases, a radio station broadcasting incorrect information may cause the RDS features of the radio to appear to work improperly.

With RDS, the radio can do the following

  1. Display text information such as: station identification, type of programming, and general information (artist and song title, station messages, call in phone numbers, etc.).
  2. Seek to stations broadcasting the selected type of programming
  3. Receive announcements concerning local and national emergencies
  4. Receive alert warnings of local or national emergencies. When an alert announcement comes on the current radio station, ALERT! displays. You will hear the announcement, even if the volume is low or a CD is playing. If a CD is playing, play stops during the announcement. Alert announcements cannot be turned off. ALERT! is not affected by tests of the emergency broadcast system. This feature is not supported by all RDS stations.

Speaker Operation

Speakers turn electrical energy into mechanical energy to move air, using a permanent magnet and an electromagnet. The electromagnet is energized when the radio or amplifier (if equipped) delivers current to the voice coil on the speaker. The voice coil will form a north and south pole that will cause the voice coil and the speaker cone to move in relation to the permanent magnet. The current delivered to the speaker is rapidly changing alternating current (A/C). This causes the speaker cone to move in two directions producing sound.

Audio Amplifier (If equipped)

Amplifier Interface

A fused battery voltage circuit provides the main amplifier power. A switched 12 V output from the radio is used to control the power - state of the amplifier. To respond quickly to audio input and control signals, the amplifier is ON in all vehicle power modes except OFF and CRANK Request. The internal amplifier bridges are fully powered and unmuted when the amplifier receives the switched 12 V input.

Amplifier Operation

The purpose of the amplifier is to increase the power of a voltage or current signal. The output signal of an amplifier may consist of the same frequencies as the input signal or it may consist of only a portion of the frequencies as in the case of a subwoofer or midrange speaker. The radio creates a low level stereo audio output signal, which is sent at the user-defined volume level to the audio amplifier. The audio amplifier amplifies the signal and sends it to the appropriate speakers. Each of the audio output channel circuits (+) and (-), from the amplifier have a DC bias voltage that is approximately one half of battery voltage. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound. The frequency (Hz) of the AC voltage signal is directly related to the frequency of the input (audio source playing) to the audio system. Both the DC bias voltage and the AC voltage signals are needed for the audio system to properly produce sound.

Theft Deterrent

The radio theft deterrent system is intended to disable or limit radio functionality if incorrect vehicle information is received by the radio. The radio disables functionality if the VIN information received by the radio does not match the VIN information that has been learned by the radio. The radio receives this information via serial data. A possible cause of incorrect VIN info could be the radio was originally installed in another vehicle.

The radio has the following theft operating modes as part of the theft deterrent system

  1. Normal Mode: The radio has learned a correct VIN sequence and the VIN information received via serial data matches the learned VIN sequence. In this mode the radio has full functionality.
  2. No VIN Mode: The radio has not received or learned a correct VIN sequence. In this mode the radio has limited functionality.
  3. Theft Detected Mode: The radio has learned a correct VIN sequence and the VIN information received via serial data does NOT match the learned VIN sequence. In this mode the radio may be disabled or have limited functionality. The radio display will indicate that theft protection is active.

Bluetooth ® (UP9) (If equipped)

Bluetooth ® wireless technology is a short-range communications technology intended to replace the cables connecting portable and/or fixed devices while maintaining high levels of security. The operating range of the signal is approximately 30 feet.

The available features and functions are determined by the type of device and the software within the devices being used. For a feature or function to operate, it must be supported in both devices.

The first connection between devices is established through a process called pairing. In order to pair two devices, a password (passkey) has to be exchanged between the two devices. One device will generate the password, the other device accepts the password to complete the process. Once the devices are paired, future connections between the devices will occur automatically when the devices are on and within range of each other.

The Bluetooth ® hardware is internal to the radio. The radio supports streaming of data (music, voice, information) from cellular phones and other mobile devices that support those features. The radio may also be capable of interfacing with cellular phones for hands-free features.

  1. The device must be paired to the radio to use the available Bluetooth ® feature(s). The pairing process must only be performed once for each device, unless that device's information is deleted.
  2. Up to five devices can be paired to the system, but only one can be connected at any given time.
  3. Streaming Audio allows playing music from the mobile device wirelessly. Music stored on the mobile device can be viewed and controlled from the display.
  4. To stream audio from a mobile device, the device must be unlocked, and any additional applications should be closed.

Refer to the vehicle owners manual, supplements, and the device manufacturers information for pairing instructions.

Applications (If equipped)

When the system is equipped with Bluetooth ®, the system may be capable of using applications, commonly referred to as apps.

The term application refers to any piece of software that works on a system (hardware) that is being operated by it's own software. Applications are typically small software programs which uses the hardware to perform a specific task, as opposed to operating the entire system.

  1. For an application to be used, it must be installed on both the vehicle infotainment system and a compatible mobile device.
  2. The device must be connected to the system. this may be done wirelessly via Bluetooth ®, or via the vehicle USB port. Refer to the device manufacturers information for the proper connection method.
  3. When the device is connected, the application on the radio is used to remotely access and control the application on the mobile device.
  4. The application must work correctly on the device to work with the vehicle infotainment system.
  5. The user may be required to log-in to the application on the mobile device before using the application from the vehicle controls.
  6. Using applications will use the device's data plan.
  7. The device must be unlocked, and any additional applications should be closed.

Refer to the owner's manual and supplements for information on mobile devices, control, and operation.

Auxiliary Audio Input Jack (If equipped)

The infotainment system may have a 3.5mm (1/8 in.) auxiliary audio input jack located in the center console. The auxiliary audio input jack may interface directly with the radio, or be connected to the infotainment system via a Multimedia Player Interface Module. When a portable audio playback device is connected to the auxiliary jack, an internal switch detects the connection and the radio will switch to AUX as the audio source. Audio signals from the device are sent to the radio from the auxiliary jack via the left, right, and common audio signal circuits.

  1. When a device is first connected to the 3.5mm (1/8 in.) input jack the infotainment system automatically switches to that device. If an auxiliary device has already been connected, press the AUX or CD/AUX button to select the device.
  2. Playback of an audio device that is connected to the 3.5mm jack can only be controlled using the controls on the device.
  3. The volume control on the device may need to be adjusted to ensure sufficient playback volume through the infotainment system.

USB Port (If Equipped)

The infotainment system may have a USB connector located in the center console. The USB connector may interface directly with the radio, or be connected to the infotainment system via a Multimedia Player Interface Module. The USB connector supports both USB standards 1.1 and 2.0.

USB Supported Devices

  1. USB Flash Sticks (Thumb Drives)
  2. Portable USB Hard Drives
  3. Portable Digital Media Players (iPOD®, ZUNE®, etc)

Depending on the USB device, some devices may not be recognized, or some features/functions may not be able to be controlled with the radio controls. USB HUB devices are not supported.

Multimedia Player Interface Module (MPIM) (If Equipped)

The vehicle may be equipped with a Multimedia Player Interface Module. This module can receive signals via the USB connector, the auxiliary audio input jack, or a Bluetooth® connection. This module receives the incoming signals, then sends the signals as analog audio inputs to the radio.

To allow the radio controls to be used to control portable media devices (USB, Bluetooth, iPOD®, ZUNE®, etc); the MPIM translates the USB signals to GMLAN signals to allow the bi-directional communication between the radio and the device. Depending on the device, some devices may not be recognized, or some features/functions may not be able to be controlled with the radio controls. USB HUB devices are not supported.

Navigation System Components and Features (if equipped)

The navigation system, if equipped, provides the following

  1. Connection to the global positioning system (GPS) antenna, which provides the vehicle position information.
  2. Route guidance with verbal prompts to the operator.
  3. Map data for navigation and map route guidance, stored on the internal hard drive.
  4. Traffic and weather information for display on the navigation system map (with active subscription, where available).

Global Positioning System (GPS) Antenna

The global positioning system (GPS) antenna is part of the multi-band antenna located on the roof of the vehicle. The GPS antenna is used to collect the signals of the orbiting GPS satellites. Within the antenna is housed a low noise amplifier that allows for a more broad and precise reception of this data. The GPS antenna amplifier is powered through the coaxial cable.

The antenna is connected to the navigation radio through a signal splitter. The signal splitter is a component for dividing the navigation signal into two paths without any transmission loss. This allows the use of a single GPS antenna to provide a signal to both the navigation radio and the telematics communication interface module.

Route Guidance

The map will display the route to the selected destination. Voice prompts alert the operator of upcoming events (turns) and arrivals at the destination. The navigation system will automatically recalculate if the route is not followed. The navigation radio uses data received from the global positioning system (GPS) satellites, the vehicle speed signal. and serial data information to accurately display the current position of the vehicle.

Points of Interest

The map database provides point of interest information. Points of interests are locations that are frequently visited. Points of interest can be can be displayed on the map or set as a destination. The following are some of the available Points of interests

  1. Gas Station
  2. Restaurant
  3. College
  4. Police Station

Traffic Information

XM NavTraffic™ is a subscription based service that enhances the navigation system with live traffic information. The service provides information on traffic conditions such as traffic speed, accidents, disabled vehicles, construction and road closings.

The integrated XM satellite radio receives the information. When Traffic Information is turned ON in the configuration menu, the available information will be displayed on the map screen.

The traffic information can vary based upon coverage in the area, and coverage is not available in all areas. No information will be displayed if coverage is not available, if there is no traffic information for the area, or if there is no subscription to receive the information.

A subscription fee is required in order to receive the XM NavTraffic™ service. No traffic data will be displayed without a current subscription.

Weather Information

XM NavWeather™ is a subscription based service that transmits weather information to the integrated XM satellite radio. Real time information such as current and future weather and road conditions, atmospheric conditions, and National Weather Service warnings is provided, as well as 3 day forecasts for some cities. Received information is available to be displayed on the Weather Info screen.

A subscription fee is required in order to receive the XM NavWeather™ service. No weather data will be displayed without a current subscription.

OnStar ® (If equipped)

When OnStar is activated, a serial data message is sent to the radio that activates a software program. When the software begins its process, the fade goes to the front, Bass and Treble are set to the mid range, the outputs are mono, and the audio source is OnStar. OnStar takes priority over any other audio source. All of these actions are preset values stored in the radio.

For additional OnStar information, refer to OnStar Description and Operation .

Steering Wheel Controls (If equipped)

Some audio functions are available using the steering wheel controls. The steering wheel controls duplicate the function of the primary controls available on the radio.

For additional information on steering wheel controls, refer to Steering Wheel Controls Description and Operation .

Auto Volume Control

With auto volume control, the audio system will adjust automatically to make up for road and wind noise as you drive, by increasing the volume as vehicle speed increases. To use auto volume control, set the volume at the desired level, and then select either Low, Medium, or High. To turn auto volume control off, select the Off screen button.

Video Entertainment System Description and Operation (Seatback Display)

Each item in the list below represents topics covered in detail below

  1. Seatback Display Circuit Operation
  2. Seatback Display System Components
  3. Video Screens
  4. Remote Control
  5. Wireless Headphones
  6. Video Inputs Only

Seatback Display Circuit Operation

Seatback Display Power

The Seatback display uses the common radio power enable voltage feed circuit and direct feed for B+ power moding.

Seatback Display Grounds

The vehicle harness provides a ground for the Seatback display system.

Seatback Display Outputs

The Seatback display can only output video to each screen.

Seatback Display Electrical Interface with Radio DVD Player

The Seatback display module will receive a video signal from the radio head unit. The left side (driver) Seatback display will receive a video signal from the radio display 1 video output. The right side (passenger) Seatback display will receive a video signal from the radio display 2 video output.

The video source sent from the radio to the video screens will be controlled via the source button on the remote control or the radio.

The Radio DVD player/Rear Seat Audio System interfaces to the display through the following

  1. Composite Video Signals NTSC and PAL video formats are supported.
  2. Left and Right Audio Signals
  3. PWM signal for Brightness Control. The brightness control is used to provide the screen brightness signal to the seatback displays. Each of the two seatback displays per vehicle share a common brightness control line from the radio The pulse width modulated (PWM) brightness control is provided by the radio over a single wire, using ground as the return.
  4. PWM signal for Mode Control. The mode control is used to control video screen display options, in support of providing different screen sizes, zoom, picture inversion and backlighting. Each of the two seatback displays per vehicle share a unique mode control signal from the radio. The PWM mode control is provided by the radio over a single wire, using ground as the return.
  5. Power Enable Signal. The power enable signal is used to activate the DVD displays.

The 2 Seatback Displays interface to the Radio DVD player through the following

IR remote data carried on a twisted wire pair. The IR remote data circuits from left and right seatback displays are spliced together within wiring harness.

Seatback Display System Components

The Seatback display system includes

  1. Two video display screens
  2. Infrared Module (located only in the left screen) Driver side transmits and receives Passenger side only receives
  3. Two sets of wireless infrared headphones
  4. A remote control
  5. Local video input for each Seatback display for playing a video auxiliary device on the Seatback display.

Scheme 47

Scheme 47: Seatback Display System Components
Scheme 47: Seatback Display System Components
CalloutComponent Name
1Left Driver Seatback Display
2Left IR-Dimly Illuminates 8 Leds, Transmits Audio And Recieves Remote Signal
3Right Passenger Seatback Display
4Right IR-LEDS Do Not Illuminate, Receives Remote Signal Only
5Local video input

Video Screen

The video screens are located in the back of the driver and front passenger seats. The rear Seatback display screen shows video from the radio DVD player, or an AUX input device, such as a video game console or camera. Only the left display console contains the infrared transmitters for the wireless headphones, they may be visible as 8 illuminated LEDs. These 8 LEDs are not on visible on the right video screen. Both consoles contain an infrared receiver for the remote control. They are located in the middle of each of the Seatback display console.

IR Module

Eight infrared light emitting diode (LED) transmitters are used to send audio signals to the wireless headphones that are included in the system. These LEDs are located on the driver's side Seatback display, and aimed to provide signal to any rear seating position. During operation, the LEDs may be visible through the lens on the driver's side display, but not on the passenger side. This is normal operation; the illuminated LEDs are located on the driver's side Seatback display only.

Remote Control

To use the remote control, aim it at the transmitter window at either the right or left seatback consoles and press the button. Direct sunlight or very bright light may affect the ability of the entertainment system to receive signals from the remote control. If the remote control does not seem to be working, the batteries may need to be replaced. Objects blocking the line of sight may affect the function of the remote control.

If a CD, DVD, or MP3 disc is in the radio DVD slot, the remote control button can be used to turn on the video screen display and start the disc. The radio can also turn on the video screen display.

If the remote control is to be stored for a long period of time, remove the batteries and keep them in a cool, dry place. Do not store the remote control in heat or direct sunlight. This could damage the remote control. Keep the remote control stored in a cool, dry place.

Wireless Headphones

Wireless headphones allow for rear seat passengers to use the display DVD without disturbing the listening of front seat passengers. The wireless headphones receive audio signals from the infrared (IR) transmitter on the left Seatback display. This transmission is line of sight only, so audio quality will be degraded if anything blocks the transmitter signal from reaching the headphones, or if the headphones are placed in the front of the vehicle. The infrared transmitter located on the left Seatback display will have red LEDs dimly illuminated when activated.

The wireless headphones include 2 channels. This allows rear seat passengers to utilize both screens individually without disturbing one another. On some wireless headphone models, you will see a red LED illuminated when the headphone is turned ON.

Each set of headphones has a rotary volume control. To adjust the volume, adjust this control. The headphones may automatically turn OFF if they lose the infrared signal from the system for approximately 4 minutes in order to preserve their battery power. The signal may be lost if the system is turned off or if the headphones are out of range of the infrared signal transmitters that are located near the video display screen.

Wireless Headphones without Rear Seat Audio (RSA)

The wireless headphones setup on the Seatback display system without Rear Seat Audio (RSA) is unique. If the RSA system is not included with vehicle, the audio that can be heard on the wireless headphone channel 2 will only be from a device (IPOD, MP3 player, game system, etc.) that is connected to the rear seat auxiliary audio jacks. Wireless headphone channel 1 will provide audio from any disc in the DVD player, including DVD audio, CD audio, and MP3 or WMA audio discs.

Video Inputs

The local video input is the standard yellow RCA color-coded jacks. The RCA jack is located on the front lower side of the Seatback display housing. Any composite video signal (from a video game, camera, stand-alone DVD player, etc.) attached to this input will override the video from the vehicle DVD or rear auxiliary jack. Power for auxiliary devices is not supplied by the radio system. To use the video input of the rear seat entertainment system, connect the auxiliary device cables to the video jacks and power ON both the auxiliary devices and the Seatback display screen. Any use of this input will have to access audio from the external device only.

Rear Seat Audio (RSA) (if equipped)

The RSA is integrated into the rear HVAC control module. Audio, video source are controlled by the radio through serial data communication. Some sources are; radio (AM/FM), XM™ (if equipped), CD, and if the vehicle has these features, DVD, front auxiliary, and rear auxiliary.

The rear speaker channels pass through the RSA. The rear seat audio can be muted by the RSA when in use.

Special Tools

Illustration Tool Number/Description EL-50334-20 Multi-Media Interface Tester (MIT) EL-50334-50 USB Cable and Adapter Kit EL-48028 Digital Radio Test Antenna EL-49903 OnStar Antenna Diagnostic Tool Kit

Scheme 48

Scheme 48: Special Tools
Scheme 48: Special Tools

Scheme 49

Scheme 49
Scheme 49

Scheme 50

Scheme 50
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Scheme 51

Scheme 51
Scheme 51

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• COMPONENT CONNECTOR END VIEWS - INDEX
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Control Module References
• Diagnostic Repair Verification
• Test Probe Caution
• Driver Information Display Replacement (With UAG)
• Inside Rearview Mirror Replacement
• Checking Aftermarket Accessories
• Diagnostic Trouble Code (DTC) List - Vehicle
• DTC U0078
• Steering Wheel Controls Malfunction
• Power Mode Mismatch
• Roof Console Replacement
• Rear Window Panel Trim Replacement (with DB3)
• Battery Negative Cable Disconnection and Connection
• Fastener Caution
• Headlining Trim Panel Replacement (with Sunroof)
• Steering Wheel Spoke Lower Cover Replacement
• RPO Code List
• Steering Wheel Controls Description and Operation
• DTC B0000
• Radio/Audio System Description and Operation
• Speaker Replacement Reference
• Video Entertainment System Description and Operation (Seatback Display)
• OnStar Description and Operation
• OnStar Steering Wheel Control Functions Malfunction
• Symptoms - Entertainment