Test D: The Auxiliary Audio Control Is Inoperative - Steering Wheel Controls

PINPOINT TEST D: THE AUXILIARY AUDIO CONTROL IS INOPERATIVE - STEERING WHEEL CONTROLS

D1-D2:

D3-D4:

D5-D6:

Normal Operation
The audio unit sends a reference voltage to the steering wheel controls through circuit 595 (LB/RD). Each steering wheel control switch function corresponds with a specific resistance value within the switch. When a switch is pressed, the audio unit monitors the change in reference voltage to determine the requested function. Ground for the steering wheel controls is provided through circuit 57 (BK).

DTC U2024 - sets when any fault is detected in the steering wheel controls circuit.

Possible Causes
- Circuit 595 (LB/RD) open or short to ground
- Circuit 57 (BK) open
- Clockspring
- Steering wheel controls
- Audio unit