Fault-Tracing Information

Condition 

No audio unit diagnostic trouble codes (DTCs) are stored in the central electronic module.

No diagnostic trouble codes (DTCs) for the rheostat are stored in the Central electronic module (CEM).

No diagnostic trouble codes (DTCs) are stored in the head unit/audio module.

Possible Source 

• Faulty rheostat value from the Central electronic module (CEM).
• Defective the head unit/audio module.

Fault symptom[s] 

• The audio equipment rheostat function is not working.