Description
The audio 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 audio unit, BOSE speaker amp. and speaker connectors for the following:
2.HARNESS CHECK



3.FRONT DOOR SPEAKER SIGNAL CHECK


4.HARNESS CHECK

connector B109.


5.FRONT DOOR SPEAKER SIGNAL CHECK


Power supply and ground circuit
TweeterPower steering solenoid valve
Description
Power steering solenoid valve controls the power steering oil pressure in the
gear housing assembly.
Diagnosis Procedure
1.CHECK POWER STEERING SOLENOID VALVE SIGNAL
Start engine.
Check voltage between power steering control unit connectorM59
terminal 1 and ground
...
Steering switch
Description
When one of the steering wheel audio control switches is pushed, the
resistance in the steering wheel audio control switch circuit changes,
depending on which button is pushed.
Diagnosis Procedure
1.CHECK STEERING SWITCH RESISTANCE
Disconnect steering switch connector M88. ...
Diagnosis system (bluetooth control unit)
Diagnosis Description
The Bluetooth control unit has two diagnostic checks. The first diagnostic
check is performed automatically every ignition cycle during control unit
initialization. The second diagnostic check is performed by the technician
using the steering wheel audio control switches ...