Pinpoint Test G: Poor Quality/Distorted/No Sound From All Speakers

Information and Entertainment System

Pinpoint Test G: Poor Quality/Distorted/No Sound From All Speakers

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

Normal Operation

The Audio Front Control Module (ACM) receives the START signal through the Controller Area Network (CAN). When it receives this signal, it mutes the audio output to prevent voltage spikes from producing a popping noise through the speakers during engine cranking.

If the ACM (Audio Front Control Module) loses power or ground, the scan tool cannot communicate with it. to continue diagnosis.

If a speaker fault DTC is set in the ACM (Audio Front Control Module), the cause of the concern is likely a short to ground or short to voltage in the circuitry to an individual speaker, which has caused the ACM (Audio Front Control Module) overload protection to activate.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- ACM (Audio Front Control Module)

PINPOINT TEST G : POOR QUALITY/DISTORTED/NO SOUND FROM ALL SPEAKERS

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

G1 CHECK FOR SPEAKER DTCs

- Ignition ON.

- Carry out the ACM (Audio Front Control Module) self-test.

Are any speaker fault DTCs present?

Yes
GO to Pinpoint Test F Pinpoint Test F: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers).

No
GO to G2.

G2 CHECK FOR CORRECT ACM (Audio Front Control Module) OPERATION

- Ignition OFF.

- 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) 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.