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For 1990-2009 cars only

Interior Lamps

The interior lighting system includes the following components:

    • The instrument panel lamp dimmer
    • The ashtray illumination lamp
    • The cigar lighter illumination lamp
    • The dome lamp
    • The reading lamps

IP Dimmer Illumination Controller


Object Number: 468541  Size: SH

Turn the parking lamps or headlamps on in order to illuminate the instrument panel and instrument panel cluster lamps. Voltage applies at all times through the TAIL fuse to the tail relay. Turning the turn signal/headlamp switch to the PARK or the HEAD position provides a ground path to the coil side of the relay to G202. The ground path energizes the coil of the relay. This closes the contacts in the relay. The closed contacts apply voltage to the IP dimmer illumination controller and all the illumination lamps. The illumination lamps are ground through the illumination controller. The controller is located on the left side of the instrument panel. Since the illumination controller is ground to G200, the lamps illuminate when voltage applies. The intensity of the instrument panel and the instrument panel cluster lamps is adjusted by the controller (4). The controller controls the intensity of the lamps by controlling the amount of current from the lamps to ground.

Rotate the dimmer control (4) upward in order to brighten the following component lamps by increasing the amount of current:

    • The instrument panel cluster
    • The heater control unit
    • The radio
    • The cigar lighter
    • The ashtray

Rotate the IP dimmer control (4) downward in order to dim the component lamps mentioned previously by decreasing the amount of current.

For information on IP dimmer illumination controller (4) removal and installation procedures, refer to Instrument Panel Lamp Dimmer Switch Replacement in Instrument Panel, Gages, and Console.

Ashtray Illumination Lamp

The ashtray illumination lamp lights whenever the parking lamps or the headlamps are activated. Refer to Ashtray Lamp Replacement for the ashtray illumination lamp removal and installation procedures.

Cigar Lighter Illumination Lamp

The cigar lighter illumination lamp lights whenever the parking lamps or the headlamps are activated. The cigar lighter illumination lamp bulb socket attaches to the rear of the cigar lighter. Refer to Cigar Lighter Housing Replacement in Instrument Panel, Gages, and Console for cigar lighter removal and installation procedures.

Dome Lamp

The front dome lamp is centered on the roof above the front seat backs. The front dome lamp consists of a clear lens, the dome lamp bulb, and a 3 position slide switch. The slide switch has the following 3 detent positions:

    • The left or OFF position
    • The center position
    • The right or ON position

The rear dome lamp on 4-door models is centered on the roof in front of the rear door opening. The rear dome lamp consists of a clear lens and a dome lamp bulb. The rear dome lamp lights and remains on until all doors are closed and the door jamb switches are open. The rear dome lamp can only be controlled by the door jamb switches.

Voltage applies at all times through the DOME fuse to the daytime running lamps (DRL) control module. The DRL control module provides voltage to the dome lamp, the rear dome lamp (4-door) and the map lamps. The dome lamp(s) ground through any of the door jamb switches. The door jamb switches, when closed (the door is open), complete a ground path for the dome lamp when the dome lamp switch is in the DOOR position. With both power and ground supplied, the dome lamp will light. The dome lamp will remain lit for approximately 15 seconds after the last door is closed (switch to its open position) and will fade out. To turn the dome lamp ON while the doors are closed, turn the dome lamp switch to the ON position. With the switch in the ON position, the ground path completes through the dome lamp. Turning the dome lamp switch to the OFF position bypasses the dome lamp circuit. The dome lamp will not light if any door is open.

The map lamp is provided a path to ground G200 when the switch is depressed. The lamp will light.

The DRL control module incorporates a battery run-down protection system. When the key is in the ignition, a signal is sent to the DRL control module. With the key in the ignition, the system is disabled. With the key removed and any of the dome or map lamps on, the DRL control module will remove the voltage supplied to the lamps in 15 minutes. This saves the vehicle battery from any unwanted discharge.

Reading Lamps

The reading lamps are on the bottom of the inside rear view mirror.

Each reading lamps consist of a clear lens, a reading lamp bulb and a ON/OFF switch. The ON/OFF switches are on the front of the inside rearview mirror near the bottom of the mirror. The lamps will light only when the switch is flipped to the right--the ON position.

The reading lamp ON/OFF switch is replaceable only as part of the inside rearview mirror assembly.