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Test E: The Audio Control Module (ACM) Does Not Respond To The Scan Tool

PINPOINT TEST E: THE AUDIO CONTROL MODULE (ACM) DOES NOT RESPOND TO THE SCAN TOOL

Normal Operation
The audio control module (ACM) communicates with the scan tool through the medium speed controller area network (MS-CAN). Circuits 1847 (WH/OG) (MS-CAN +) and 1848 (PK/OG) (MS-CAN -) provide the network connection to the ACM. The ACM shares the MS-CAN with the smart junction box (SJB), the SDARS module (if equipped), and the instrument cluster (IC). Voltage for the ACM is provided by circuits 687 (GY/YE) and 729 (RD/WH). Circuit 1204 (BK/OG) provides ground.

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals and connectors
- ACM


E1-E2:






E3-E4: