Principles of Operation
Dimmable Backlighting
The lighting control module (LCM) generates a variable pulse width modulated (PWM) voltage and the driver door module (DDM) generates a variable voltage which is distributed to the dimmable components when the headlamp switch is in the PARKING LAMPS or HEADLAMPS ON positions. Note: the DDM provides the variable voltage to the heating ventilation air conditioning (HVAC) module and overhead console with moonroof only. Light intensity is adjusted by rotating the instrument panel dimmer switch. The dimmable backlighting components consist of:
- Adjustable pedal switch
- Audio unit
- HVAC module (if equipped)
- Climate control assembly (manual temperature control) (if equipped)
- Traction control switch (if equipped)
- Floor shifter (if equipped)
- Headlamp switch
- Heated rear window switch
- Message center switch
- Overhead console
- Steering wheel speed control switches
- Steering wheel audio/climate control switches
The LCM communicates backlighting intensity signals on the standard corporate protocol (SCP) network to the instrument cluster (IC) and the DDM.
Fixed Level Backlighting
The following components have fixed level backlighting that is illuminated when the ignition switch is in the RUN or ACCESSORY position:
- Driver window control switch
- Passenger window control switch
- RH rear window control switch
- LH rear window control switch
- Driver door lock control switch
- Passenger door lock control switch
- Driver heated seat control switch
- Passenger heated seat control switch