Circuit Description
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The body control module (BCM) receives a variable voltage signal from the instrument panel (I/P) dimmer switch requesting to illuminate the dimming lamps to a desired intensity. When this occurs, the BCM directly sends a pulse width modulated (PWM) voltage based on the I/P dimmer switch position on the LED dimming signal circuit, instrument panel lamps dimming control circuit, and the backlight lamps control circuit.
Voltage for the LED dimming signal circuit, instrument panel lamps dimming control circuit, and the backlight lamps control circuit is from the TBC 3 fuse 16 in the underhood fuse block directly through the BCM to these circuits.