Principles of Operation

The instrument panel dimmer switch uses electronic circuitry to provide a variable pulse width modulation (PWM) output to the dimmer module, instrument cluster and auxiliary A/C controls depending upon the driver-controlled level of intensity. The dimmer module monitors the input level from the instrument panel dimmer switch and provides a PWM low output to the audio unit, dual automatic temperature control (DATC) and transmission range selector lever depending on the driver setting.

The dimmer module also monitors sunload sensor input, and uses this input, with the PWM input from the instrument panel dimmer switch, to provide a PWM, high output to the:

• clock
• headlamp switch
• adjustable pedal switch
• digital versatile disc (DVD)
• memory seat switch
• steering wheel control switches
• message center switch
• interactive vehicle dynamics (IVD) switch (depending on driver setting and outside light conditions)