PINPOINT TEST M : THE AUDIO CONTROL MODULE (ACM) DOES NOT RESPOND TO THE
DIAGNOSTIC SCAN TOOL
M1 CHECK THE ACM (AUDIO FRONT CONTROL MODULE) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
Ignition OFF. Disconnect: ACM C240A. Ignition ON. Measure:
Click to display connectors
Positive Lead | Measurement / Action | Negative Lead |
|---|---|---|
C240A-1 | Ground |
Is the voltage greater than 11 volts?
Yes | GO to M2 |
|---|---|
No | VERIFY the BCM fuse 33 (20A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short. |
M2 CHECK THE ACM (AUDIO FRONT CONTROL MODULE) GROUND CIRCUIT FOR AN OPEN
Ignition OFF. Measure:
Click to display connectors
Positive Lead | Measurement / Action | Negative Lead |
|---|---|---|
C240A-13 | Ground |
Is the resistance less than 3 ohms?
Yes | GO to M3 |
|---|---|
No | REPAIR the circuit. |
M3 CHECK THE HS-CAN3 (HIGH SPEED-CONTROLLER AREA NETWORK 3) CIRCUITS BETWEEN THE ACM (AUDIO FRONT CONTROL MODULE) AND THE GWM (GATEWAY MODULE A) FOR AN OPEN
Disconnect GWM C2431. Measure:
Click to display connectors
Positive Lead | Measurement / Action | Negative Lead |
|---|---|---|
C240A-14 | C2431-16 | |
C240A-15 | C2431-15 |
Are the resistances less than 3 ohms?
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.