Diagnosis Procedure
1.CHECK CONNECTOR
2.CHECK HARNESS FOR OPEN CIRCUIT
Check the resistance between the data link connector terminals.

BCM branch line circuit
M&A branch line circuitU122A AV control unit
DTC Logic
Diagnosis Procedure
1.PERFORM THE SELF-DIAGNOSIS
When U122A is detected, write configuration data with "MULTI AV" of CONSULT.
U122E AV CONTROL UNIT
DTC Logic
DTC DETECTION LOGIC
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Symptom diagnosis
ADP SYSTEM SYMPTOMS
Symptom Table
SYMPTOM 1
SYMPTOM 2
SYMPTOM 3
SYMPTOM 4
SYMPTOM 5
NORMAL OPERATING CONDITION
Description
The following symptoms are normal operations, and they do not indicate a
malfunction.
...
Front door speaker
Description
The AV control unit sends audio signals to the BOSE speaker amp. The BOSE
speaker amp. amplifies the
audio signals before sending them to the front door speakers using the audio
signal circuits.
Diagnosis Procedure
1.CONNECTOR CHECK
Check the AV control unit, BOSE speaker amp. ...