Instrument Panel Illumination
PANEL LAMPSWhen the Park Lamps or Headlamps are turned "ON," voltage is applied to terminals "0" and "B" of the Incandescent Power Driver. The Incandescent Power Driver is a solid state device. When these two voltages are present, the Incandescent Power Driver allows voltage to be applied through the H INST Fuse for Panel Lamps on the RH side of the vehicle, and through the L INST Fuse for Panel Lamps on the LH side of the vehicle.
The Panel Lamps are dimmed by using the Dimmer Rheostat at the Light Switch. The Dimmer Rheostat controls the voltage applied to terminal "B" of the Incandescent Power Driver (the lower the voltage - the dimmer the Panel Lamps). This voltage at terminal "B" is "transferred" through the Incandescent Power Driver to the Panel Lamps.
Ground for the Panel Lamps is provided by 0201 and G202.
LED LIGHTING
The LED dimming and LCD dimming is controlled by the Central Control Module (CCM).
When the Park Lamps or Headlamps are turned "ON," voltage is applied to the CCM by the Park Lamp Circuit (CKT 9) and the Dimmer Rheostat Circuit (CKT 1370). When the CCM receives these voltages, a digital signal is sent to the various LED and LCD devices. The digital signal is variable, depending upon the position of the Dimmer Rheostat at the Light Switch.
The Central Control Module will set Codes 71, 72, 73 or 74 if a problem exists in the LED and LCD dimming circuits.