Interior Lamps Dimming

VF DISPLAYS
When the ignition switch is turned to the RUN position, the instrument cluster activates its VF display. The instrument cluster also coordinates the display illumination for the Radio (IRC), the Cellular Telephone (PHN). and the Climate Control Panel (CCP) anytime the ignition switch is in the RUN position.

INCANDESCENT DIMMING 1 (INC DIM 1)
The INC DIM 1 output consists of the lamps powered by CKT 8 (GRY). They are referred to as the park lamp backlighting, because they are only active if the park lamps are on and the ambient light sensor indicates darkness.

INCANDESCENT DIMMING 2 (INC DIM 2)
The INC DIM 2 output is used as a general interior light source and an illuminated entry feature that provides interior lighting. INC DIM 2 consists of lamps powered by CKT 1244 (BRN). When one or more of the following conditions occur, the INC DIM 2 lamps will be active:
^ Interior lamps switch is active.
^ Park lamps are on and the ambient light sensor indicates darkness.
^ Ignition switch is in RUN and the ambient light sensor indicates darkness.
^ A Class 2 message is received from the body control module (PZM) indicating that the courtesy lamps are active.

DIMMING
The instrument cluster controls all interior dimming functions. The instrument cluster receives an ambient light level input from the ambient light sensor and determines whether it is light or dark. If the ambient light sensor is inoperative, the instrument cluster will assume a condition of darkness. Dimming of the VF displays is only allowed when the ignition switch is in RUN. the park lamps are on, and the ambient light sensor indicates darkness. If all conditions for VF dimming are met, the instrument cluster uses the input from the potentiometer in the headlamp switch to determine the level of dimming. The dimming level is sent to the IRN, the PHN. and the CCP via a Class 2 message. These nodules then adjust the dimming level of their VF display. The instrument cluster provides dimming control of the incandescent lighting through the INC DIM 1 and INC DIM 2 outputs. The instrument cluster provides dimming control of the electronic PRNDL LED via CKT l382 (PPL/WHT). The dimming level will vary based on the potentiometer in the headlamp switch whenever the park lamps are on and the ambient light sensor indicates darkness, regardless of the position of the ignition switch.