Test E: The Steering Wheel Controls Are Inoperative/Do Not Operate Correctly
PINPOINT TEST E: THE STEERING WHEEL CONTROLS ARE INOPERATIVE/DO NOT OPERATE CORRECTLYNormal Operation
Voltage is sent from the audio unit to the steering wheel controls through circuit VME14 (GY/YE). When a switch is pressed, the voltage is routed through a specific resistor value for each function. The audio unit grounds the reference voltage through circuit RMC27 (WH/BN). The audio unit uses this reference voltage to determine which control input function has been selected.
DTC B1117 (Audio Steering Wheel Button Stuck) - sets when a steering wheel control switch is detected as active for more than 120 seconds during normal operation, or for any duration during the self-test. A short to ground on circuit VME14 (GY/YE) or RMC27 (WH/BN) should not set this DTC, as the reference voltage would fall out-of-range, resulting in DTC B1136 or B2404 being set.
DTC B1136 (Audio Steering Wheel Switch #2 Circuit Failure) - sets when the return voltage from the steering wheel controls is out-of-range, either during normal operation or during the on-demand self-test. This can be caused by any failure on the steering wheel controls circuit except a stuck button. This DTC is only set by the navigation audio unit.
DTC B2404 (Audio Steering Wheel Switch Circuit Fault) - sets when the return voltage from the steering wheel controls is out-of-range, either during normal operation or during the on-demand self-test. This can be caused by any failure on the steering wheel controls circuits except a stuck button.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Clockspring
- Steering wheel controls
- Audio unit