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Pinpoint Test B: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers) - Vehicles With Bench Seat




Information and Entertainment System

Pinpoint Test B: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers) - Vehicles With Bench Seat

Refer to Wiring Diagram Set 130, Audio System/Navigation for schematic and connector information Electrical Diagrams.

Normal Operation

The Audio Front Control Module (ACM) directs audio signals to the speakers in the form of an AC voltage. The ACM (Audio Front Control Module) provides internal circuit protection for shorts to ground or shorts to voltage.

A short to ground or short to voltage in the circuitry to one of the speakers may cause multiple speakers to lose sound due to the built-in overload protection feature of the ACM (Audio Front Control Module). In this case, a speaker fault DTC sets, and this pinpoint test should be followed to isolate the damaged circuit.

It should also be noted that when the ACM (Audio Front Control Module) activates the built-in overload protection, DTC B1342 may also be set. The circuit failure must be repaired before DTC B1342 can be cleared.

The speaker walk test can be used to isolate a concern with a particular speaker. This can reduce the diagnostic steps necessary to isolate the concern. To carry out the speaker walk test, refer to Audio Control Module (ACM) Self-Diagnostic Mode Service and Repair.

- DTC B2965 (Audio System Speaker Circuit Fault)- sets when an open, short to ground, or short to voltage is detected on any of the speaker circuits.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Speaker

- ACM (Audio Front Control Module)

PINPOINT TEST B : POOR QUALITY/DISTORTED/NO SOUND FROM ONE OR MORE SPEAKERS (NOT ALL SPEAKERS) - VEHICLES WITH BENCH SEAT

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

B1 DETERMINE THE INOPERATIVE SPEAKER

- Ignition ON.

- Carry out the speaker walk test. Refer to Audio Control Module (ACM) Self-Diagnostic Mode Service and Repair.

Is the concern only with a tweeter speaker?

Yes
GO to B2.

No
GO to B5.

B2 CHECK THE AUDIO SIGNALS TO THE SUSPECT TWEETER SPEAKER

- Ignition OFF.

- Disconnect: Suspect Tweeter Speaker.

- Operate the audio system in radio tuner (AM/FM) mode.

- Measure the AC voltage between the suspect tweeter speaker pin 1 and pin 2, harness side as follows:

Suspect Speaker Positive Meter Lead Negative Meter Lead LH tweeter C513-1 VME08 (GN/OG) C513-2 RME08 (GY/OG) RH tweeter C613-1 VME11 (VT/OG) C613-2 RME11 (YE/OG)






Is a fluctuating AC voltage present?

Yes
INSTALL a new speaker for the suspect tweeter speaker. REFER to Speaker - Door . CLEAR any DTCs present. TEST the system for normal operation.

No
GO to B3.

B3 CHECK THE CIRCUITS TO THE SUSPECT TWEETER SPEAKER FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: LF Door Speaker C523B (LH Speaker Concern) or RF Door Speaker C612B (RH Speaker Concern).

- Ignition ON.

- Measure the voltage between the suspect tweeter speaker, harness side and ground as follows:

Suspect Tweeter Speaker Positive Meter Lead Negative Meter Lead LH tweeter C513-1 VME08 (GN/OG) Ground C513-2 RME08 (GY/OG) Ground RH tweeter C613-1 VME11 (VT/OG) Ground C613-2 RME11 (YE/OG) Ground






Is any voltage present?

Yes
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

No
GO to B4.

B4 CHECK THE CIRCUITS TO THE SUSPECT TWEETER SPEAKER FOR AN OPEN OR SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the suspect tweeter speaker, harness side and the respective door speaker, harness side; and between the suspect tweeter speaker, harness side and ground as follows:

Suspect Tweeter Speaker Positive Meter Lead Negative Meter Lead Circuit LH tweeter C513-1 C523B-1, then ground VME08 (GN/OG) C513-2 C523B-2, then ground RME08 (GY/OG) RH tweeter C613-1 C612B-1, then ground VME11 (VT/OG) C613-2 C612B-2, then ground RME11 (YE/OG)






Is the resistance less than 5 ohms between the suspect tweeter speaker and the door speaker, and greater than 10,000 ohms between the suspect tweeter speaker and ground?

Yes
INSTALL a new door speaker. REFER to Speaker - Door . CLEAR any DTCs present. TEST the system for normal operation.

No
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

B5 CHECK THE AUDIO SIGNALS TO THE SUSPECT SPEAKER

- Ignition OFF.

- Disconnect: Suspect Speaker.

- Operate the audio system in radio tuner (AM/FM) mode.

- Measure the AC voltage between the suspect speaker pins, harness side as follows:

Suspect Speaker Positive Meter Lead Negative Meter Lead LF door C523A-1 VME07 (WH) C523A-2 RME07 (WH/BN) RF door C612A-1 VME10 (WH/VT) C612A-2 RME10 (WH/OG) LR door C702-1 VME12 (BN/WH) C702-2 RME12 (BN/BU) RR door C802-1 VME12 (BN/WH) C802-2 RME12 (BN/BU)






Is a fluctuating AC voltage present?

Yes
INSTALL a new speaker for the suspect speaker. REFER to Speaker - Door . CLEAR any DTCs present. TEST the system for normal operation.

No
GO to B6.

B6 CHECK THE CIRCUITS TO THE SUSPECT SPEAKER FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: ACM (Audio Front Control Module) C240A.

- Ignition ON.

- Measure the voltage between the suspect speaker, harness side and ground as follows:

Suspect Speaker Positive Meter Lead Negative Meter Lead LH front C523A-1 VME07 (WH) Ground C523A-2 RME07 (WH/BN) Ground RH front C612A-1 VME10 (WH/VT) Ground C612A-2 RME10 (OG) Ground LH rear C702-1 VME12 (BN/WH) Ground C702-2 RME12 (BN/BU) Ground RH rear C802-1 VME12 (BN/WH) Ground C802-2 RME12 (BN/BU) Ground






Is any voltage present?

Yes
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

No
GO to B7.

B7 CHECK THE CIRCUITS TO THE SUSPECT SPEAKER FOR AN OPEN OR SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the ACM (Audio Front Control Module), harness side and the suspect speaker, harness side; and between the ACM (Audio Front Control Module), harness side and ground as follows:

Suspect Speaker Positive Meter Lead Negative Meter Lead LH front C240A-8 VME07 (WH) C523A-1, then ground VME07 (WH) C240A-21 RME07 (WH/BN) C523A-2, then ground RME07 (WH/BN) RH front C240A-11 VME10 (WH/VT) C612A-1, then ground VME10 (WH/VT) C240A-12 RME10 (WH/OG) C612A-2, then ground RME10 (WH/OG) LH rear C240A-9 VME09 (WH/GN) C702-1, then ground VME12 (BN/WH) C240A-22 RME09 (BN/YE) C702-2, then ground RME12 (BN/BU) RH rear C240A-10 VME12 (BN/WH) C802-1, then ground VME12 (BN/WH) C240A-23 RME12 (BN/BU) C802-2, then ground RME12 (BN/BU)






Is the resistance less than 5 ohms between the ACM (Audio Front Control Module) and the suspect speaker, and greater than 10,000 ohms between the ACM (Audio Front Control Module) and ground?

Yes
GO to B8.

No
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

B8 CHECK FOR CORRECT ACM (Audio Front Control Module) OPERATION

- Ignition OFF.

- Connect: All Disconnected Connectors.

- Disconnect all the ACM (Audio Front Control Module) connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the ACM (Audio Front Control Module) connectors and make sure they seat correctly.

- Operate the system and determine if the concern is still present.

Is the concern still present?

Yes
INSTALL a new ACM (Audio Front Control Module). REFER to Audio Control Module (ACM) . TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR any DTCs present.