Exterior Lighting

EXTERIOR LIGHTING

NOTE: The smart junction box (SJB) is also known as the generic electronic module (GEM).

Headlamps
The headlamp system is a dual-beam pattern system. It consists of a low and high beam, with a replaceable bulb. The headlamp assembly has the park/turn indicator lamp integrated into the headlamp assembly. The SJB supplies voltage to the headlamps when demanded.

Autolamps
The autolamp system provides light sensitive automatic on/off control of the exterior lamps. The autolamp system keeps the exterior lamps on for a pre-selected period of time after the ignition switch is turned to the OFF position. The pre-selected time lapse is adjustable up to approximately 3 minutes.

To program the time delay, refer to Autolamps Time Delay Adjustment.

Vehicles equipped with autolamps also have a feature that turns on the exterior lamps when the windshield wipers are turned on.

Stoplamps
The high mounted stoplamp and rear stoplamps are supplied voltage when the brake pedal is applied.

Turn Signal/Hazard Lamps
The front turn signal lamps are located within the headlamp assemblies. When the multifunction switch is placed in the LH or RH TURN positions, the SJB routes voltage to the LH or RH turn signal lamps. The SJB then cycles the voltage on and off approximately 80 times per minute. If a front or rear turn bulb is inoperative, the SJB cycles the voltage on and off approximately 160 times per minute for bulb outage indication.

The hazard switch is integral to the multifunction switch. When the hazard switch is engaged, the SJB supplies voltage to all the turn lamps. The SJB cycles the voltage on and off approximately 80 times per minute.

Parking Lamps
The SJB supplies voltage to the parking lamps when demanded. The front parking lamps are located in the headlamp assemblies. The rear parking lamps are located in the rear lamp assemblies.

Fog Lamps
The fog lamp switch is integral to the headlamp switch. When the fog lamp switch is engaged, the fog lamp relay is energized and routes voltage to the fog lamps. The fog lamps can be turned on when the ignition switch is in the RUN or ACC position, the low beam headlamps are on, and the high beam headlamps are off.

Reversing Lamps
When the transmission is placed in REVERSE (R), the SJB provides a ground for the reversing lamp relay coil (internal to the SJB). The reversing lamps receive voltage when the reversing lamp relay is energized. The reversing lamps are located within the rear lamp assemblies.

Trailer Tow
The SJB supplies voltage to the trailer tow stop/turn, parking and reversing lamps. When the vehicle's rear stop/turn lamp, parking lamps, or reversing lamps are illuminated, voltage is supplied to the trailer tow connector.

The trailer tow battery charge relay provides voltage to the trailer tow connector when the ignition switch is in the RUN or ACC position.

The vehicle comes equipped with circuitry to support trailer tow electric brakes.

Daytime Running Lamps (DRL)
The DRL system operates the low beam headlamps at a reduced intensity. The SJB supplies pulse width modulated (PWM) voltage to illuminate the low beam headlamps at a reduced intensity when the following conditions are met:
- The headlamp switch is not in the HEADLAMPS ON position.
- The ignition switch is in the RUN position.
- The transmission is not in PARK (P).