Principles of Operation
PRINCIPLES OF OPERATIONWhen the audio unit is powered up, a fluctuating AC voltage audio signal is sent from the audio unit to the speakers to produce sound. For vehicles equipped with an optional subwoofer, when the audio unit is powered up, a wake-up signal is sent to the subwoofer amplifier. Audio output signals are then sent continuously to the subwoofer amplifier. These signals are amplified and sent to the subwoofer speakers as a fluctuating AC voltage.
The steering wheel controls consist of a series of resistors. 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.
The audio unit has a self-diagnostic mode that can be entered by pressing specific preset buttons simultaneously. For additional information, refer to Speaker walk-Around Test and the Audio Control Module Self-Diagnostic Mode. Component Tests and General Diagnostics Reading and Clearing Diagnostic Trouble Codes