Test A: No Communication With The Audio Unit

PINPOINT TEST A: NO COMMUNICATION WITH THE AUDIO UNIT

A1-A2:

Normal Operation
Voltage is supplied to the audio unit at all times through circuit 1111 (VT). Accessory delay voltage is supplied to the audio unit through circuit 1006 (DG/WH). The audio unit is grounded through circuit 1204 (BK/OG). Communication with the audio unit is provided over the controller area network (CAN) through circuits 2180 (WH/BK) and 2181 (BK/YE).

Possible Causes
- Fuse
- Circuit 1006 (DG/WH) open
- Circuit 1111 (VT) open
- Circuit 1204 (BK/OG) open
- Communications network
- Audio unit