GM Service Manual Online
For 1990-2009 cars only

Headlamps

The headlamps consist of 2 interchangeable single filament bulbs that provide high and low beams. The inner bulb in the headlamp is the high beam and the outer bulb is the low beam.

Headlamp Switch

The headlamp switch is located to the left of the instrument cluster. The headlamp switch includes controls for the following components:

    • The park lamps
    • The headlamps
    • The fog lamps
    • The twilight sentinel
    • The interior dimming
    • The export position lamps

Ambient Light Sensor

The ambient light sensor is located on the left side of the defroster grille. The ambient light sensor is a variable resistor that changes as the light level through the windshield changes. Daylight or nighttime conditions is determined by the value of the ambient light sensor. If an object is covering the ambient light sensor, the vehicle may act as if nighttime conditions exist even though it is daytime.

Front Fog Lamps

The front fog lamps consist of 2 clear bulbs. Each bulb is located below the front bumper fascia. The front fog lamps provide additional lighting during foggy driving conditions.

Rear Fog Lamps

The rear fog lamps are available on export vehicles only. The rear fog lamps consist of 2 red bulbs. Each bulb is located in the rear compartment lid lamp assembly. The rear fog lamps provide additional rear lighting during foggy driving conditions.

Front Park/Side Marker/Turn/Cornering Lamps

The front park, side marker, turn signal, cornering lamp are all an integral part of the headlamp assembly. The side marker lamp is amber in color and contains reflectors in order to alert approaching vehicles for nighttime driving safety. The cornering lamp is clear and lights the peripheral turn area of the vehicle.

Tail Lamps

The tail, stop, and turn signal functions are performed by the quarter mounted tail lamps and rear compartment lid assembly tail lamps. The quarter mounted tail lamp consists of a red lens, a tail/stop lamp bulb, and a turn lamp. The vehicle does not have separate rear side marker lamps. The quarter mounted tail lamp wraps around the corner of the vehicle and serves as the rear side marker function. The lower portion of the lamp contains reflectors in order to alert approaching vehicles for driving nighttime safety. The rear compartment lid lamp assembly consists of 4 tail lamp bulbs, 2 backup lamp bulbs, and 2 license lamp bulbs.

Center High Mounted Stop Lamp (CHMSL)

The center high mounted stop lamp (CHMSL) is located along the rear compartment lid. The CHMSL operates simultaneously with the rear stop lamps and provides increased visibility of vehicle braking.

License Lamps

The license lamps consist of 2 clear bulbs. The bulbs are located in the rear compartment lid lamp assembly. The license lamps illuminate the license plate of the vehicle when the park lamps are on.

Repeater Lamps

The repeater lamps are on export vehicles only. Each lamp is located in the front fender. The repeater lamps are used as additional turn signal lamps for export vehicles.

Position Lamps

The position lamps are on export vehicles only. Each lamp is located in the headlamp assembly. European countries require that side position lamps are activated when the vehicle is parked along the side of the road. The position function will operate only with the gear selector in the PARK position. The front position lamp and 1 tail lamp on the one side are lit during the position function.

Hazard Lamps

The hazard switch is located in the instrument panel to the right of the steering column. The hazard function uses all of the left and the right turn lamps.

Stoplamp/BTSI Switch

The stoplamp/BTSI switch is located under the instrument panel, near the top of the brake pedal.

Backup Lamps

The backup lamps are white, located in the rear compartment lid lamp assembly. The backup lamps provide rear lighting and alert others when the vehicle is in reverse.

Reading Lamps

There are 3 reading lamps located in the overhead console and 2 reading lamps located in the rear of the headliner. Each reading lamp has a switch that is used in order to turn the reading lamp on and off.

Courtesy Lamps

Courtesy lamps are located in the driver foot well and passenger foot well. There is also a courtesy lamp located in each door. The reading lamps are also used as courtesy lamps. Courtesy lamps are used in order to illuminate the vehicle during nighttime conditions. The courtesy lamps are divided into front and rear. The front courtesy lamps include the front foot well lamps, all door courtesy lamps, and the reading lamps in the overhead console. The rear courtesy lamps include the rear reading lamps in the headliner. The lamps may also be manually turned on or off using the interior lamp switch.

Interior Lamp Switch

The interior lamp switch is located in the overhead console. The interior lamp switch is used in order to control the courtesy lamps.

Underhood Lamp

The underhood lamp is located in the engine compartment, on the left rear of the hood.

Rear Compartment Lamp

The rear compartment lamp is located in front center of the rear compartment.

Vanity Lamps

The vanity lamps are located in the center of each sunshade.

IP Compartment Lamp

The IP compartment lamp is located in IP compartment on the right side of the instrument panel.

Ignition Key Cylinder Lamp

The ignition key cylinder lamp is located in the instrument panel to the right of the steering column. This lamp aids the driver in locating the ignition switch in order to insert their key. The lighting of the ignition key cylinder lamp is controlled by the instrument panel integration module (IPM).

Interior Lamps Dimming

The instrument cluster (IPC), radio, cellular telephone, and heater and A/C control assembly all have vacuum fluorescent (VF) displays, if equipped. The incandescent lamps include the following components:

    • The ashtray lamp
    • The rear blower switch
    • The PRNDL lamp
    • The traction control switch
    • Four heated seat switches
    • The steering wheel controls
    • Two driver information center (DIC) switches
    • The release switch assembly
    • The headlamp switch
    • The radio
    • The heater and A/C control assembly
    • Four power window switches
    • Four power door lock switches
    • The memory function switch, if equipped

The incandescent lamps and VF displays may be dimmed in order to change the amount of light inside the vehicle.