The interior lighting consist of the following 2 groups. This first group includes lamps that may not be dimmed.

The courtesy/illuminated entry lamps, may be manually turned on or off by placing the interior lamp switch in the ON or OFF position. If a door is opened, the courtesy/illuminated entry lamps illuminate. After all the doors have been closed the courtesy/illuminated entry lamps will remain illuminated approximately 15 seconds. The courtesy/illuminated entry lamps will also turn on prior to any door being opened, and remain illuminated approximately 40 seconds when the driver removes the ignition key. If the interior lamp switch is turned on when the ignition key is OFF, or the interior lamp switch is left on when the ignition key is turned OFF the body control module (BCM) will turn off the courtesy lamps after approximately 10 minutes.

When the driver places the dome lamp defeat switch in the OFF position, the courtesy/illuminated entry lamps will be disabled; however, the lamps will still operate from the interior lamp switch.

The left and right front door courtesy lamps are controlled, and receive voltage and ground from the drivers door module (DDM) and the passenger door module (PDM), respectively. The BCM, DDM, and the PDM communicate through GMLAN serial data circuit for the lamp illumination commands and the door ajar switches.

When the driver uses the door key in order to unlock the doors, the body control module (BCM) receives a door unlock signal. The BCM must have inputs or serial data messages that indicate that the ignition switch is OFF, the courtesy lamp switch is OFF and all the doors are closed. The BCM will then activate the interior lamps. The courtesy lamps will remain ON, approximately 15 seconds after the door is closed. The BCM will then turn them OFF through the theater dimming feature. If the door locks are activated to the LOCK position, or if the ignition switch is turned to either the RUN or CRANK position the courtesy lamps will turn OFF immediately.

When the driver uses the remote function actuator transmitter to unlock the doors, or presses the panic button, the BCM will keep the courtesy lamps on approximately 40 seconds. When the driver uses the remote function actuator transmitter to lock the doors, the BCM will keep the courtesy lamps on approximately 2 seconds. If the ignition switch is turned to either the RUN or CRANK position, the courtesy lamps will turn off immediately. The BCM will also keep the courtesy lamps on approximately 40 seconds, after an alarm event is completed.

The inadvertent power supply voltage circuit of the body control module (BCM) provides battery positive voltage to each vanity mirror lamp. When the vanity mirror cover on the sunshade is opened, a switch closes to provide a ground circuit and the vanity lamp illuminates. In the event that any of these lamps were to remain illuminated for a period of more than 10 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power supply voltage circuit to prevent a total battery discharge condition. Ground is provided to the vanity lamps at G203.

The inadvertent power supply voltage circuit of the body control module (BCM) provides battery positive voltage to the instrument panel (I/P) compartment lamp. When the I/P compartment is opened, a switch closes to provide a ground circuit and the I/P compartment lamp illuminates. In the event that any of these lamps were to remain illuminated for a period of more than 10 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power supply voltage circuit to prevent a total battery discharge condition. Ground is provided to the I/P compartment lamp at G203.

The inadvertent power supply voltage circuit of the body control module (BCM) provides battery positive voltage to the reading lamps. The reading lamps and switch are integral to the courtesy/reading lamp assembly. When the switch is closed, voltage is supplied and the lamp illuminates. In the event that any of these lamps were to remain illuminated for a period of more than 10 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power supply voltage circuit to prevent a total battery discharge condition. Ground is provided to the reading lamps at G203.

The body control module (BCM) inadvertent power supply voltage circuit provides battery positive voltage to all of the interior reading lamps, instrument panel (I/P) compartment lamp, and both visor vanity mirror lamps. In the event that any of these lamps were to remain illuminated for a period of more than 10 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power supply voltage circuit to prevent a total battery discharge condition.

The BCM also utilizes the inadvertent power supply voltage circuit as a lamp request signal circuit when none of the lamps in the circuit are illuminated. When a lamp switch is activated, the BCM receives the request for lamp illumination and switches to supplying voltage to the inadvertent power supply voltage circuit.

The second group includes lamps which may be dimmed. This group may use a combination of vacuum fluorescent (VF) illumination and incandescent lamps.

When the ignition switch is turned to the RUN position, the radio's VF displays turn on at maximum brightness. When the park lamps are on, all incandescent back lighting turns on at the dimming level indicated by the instrument panel (I/P) dimmer switch. At the same time all VF displays dim to match the indicated dimming level. The panel dimmer switch potentiometer is an input to the body control module (BCM). When the driver selects a dimming setting by moving the I/P dimming switch potentiometer, all incandescent back lighting lamps are provided with a specific voltage. When the I/P dimmer switch is moved from MIN to MAX, all VF displays, as well as all incandescent back lighting, respond from minimum intensity to maximum brightness in response to the I/P dimmer switch. The following switches and components have back lighting when the park lamps are on.

The left and right front door switch illumination is controlled, receives voltage and ground from the driver door switch and passenger switch respectively. The radio is also a GMLAN module and has full control of its illumination. The BCM, door switches, and radio communicate through GMLAN serial data for the lamp illumination commands.

The I/P cluster illumination lamps receive voltage and are controlled by the BCM on the instrument panel lamps dimming supply voltage circuit. Ground for the instrument panel lamps is at G203.

The various switches, HVAC control assembly, and the PRNDL lamps receive voltage, and are controlled by the BCM on the instrument panel lamps dimming control circuit. Ground for the rear window switches is at G302 and G306. Ground for the traction control switch, steering wheel controls, and the rear window/wiper switch is at G200. Ground for the remaining switches is at G203.

The following indicators receive voltage from the BCM and are controlled by various modules.

The indicators receive voltage from the BCM on the LED dimming circuit. Ground/control for the indicators is from the various modules. The modules controlling the above indicators are as follows: