Operation CHARM: Car repair manuals for everyone.

Principles of Operation




Instrument Cluster and Panel Illumination

Principles of Operation

Dimmable Backlighting

The dimmable illumination is controlled by the instrument panel dimmer switch, which allows the brightness level of the backlights to be adjusted to the customer preferences. With the side, main or parking lamps on, the instrument panel dimmer switch uses electronic circuitry to provide a variable Pulse Width Modulated (PWM) output to the Instrument Cluster (IC), Audio Control Module (ACM), the climate control assembly and all dimmable backlit switches depending on the driver-controlled level of intensity.

Fixed Backlighting

The non-dimmable illumination allows for full intensity when the ignition switch is in the ON position.