Exterior Lighting
Exterior Lighting
NOTE: The cargo lamp and running board lamps are covered in Lighting and Horns.
Battery Saver
NOTE: Time-out is 1 minute if the vehicle has less than 80 km (50 miles).
The battery saver is internal to the Body Control Module (BCM) and provides automatic shut-off of the headlamps and parking lamps after 10 minutes in order to save battery voltage. A timer is started when the ignition switch is changed to the OFF state with the headlamp switch in the HEADLAMPS ON position, or the headlamp switch is placed in the HEADLAMPS ON position with the ignition switch off. When 10 minutes have elapsed, the voltage is automatically shut off to the lamps by the BCM (Body Control Module).
The battery saver does not control the parking lamps if the headlamp switch is in the PARKING LAMPS ON position.
The timer restarts (and voltage is restored if the BCM (Body Control Module) had the voltage disabled) if any of the following occurs:
- The ignition state is changed to any state other than OFF.
- The headlamp switch position changes.
- Any door becomes ajar.
- The UNLOCK button of the Remote Keyless Entry (RKE) transmitter is pressed.
- A valid keypad code is entered.
- The instrument panel dimmer switch is pressed
Lamp Assembly Condensation
Exterior lamps are vented to accommodate normal changes in pressure. Condensation can be a natural by-product of this design. When moist air enters the lamp assembly through the vents, there is a possibility that condensation can occur if the temperature is cold. When normal condensation occurs, a thin film of mist can form on the interior of the lens. The thin mist eventually clears and exits through the vents during normal operation. Time to clear the lens of acceptable mist varies with ambient humidity and lamp types. Normal condensation clears from any lamp in 48 hours under dry conditions.
Do NOT replace a lamp assembly with acceptable levels of condensation such as:
- presence of thin mist (no streaks, drip marks or droplets are present)
- fine mist covers less than 50% of the lens
Examples of unacceptable moisture (usually caused by a lamp housing leak):
- water puddling inside the lamp
- large water droplets, drip marks or streaks present on the interior of the lens
Headlamps
The headlamp system consists of the following components:
- Headlamps
- Headlamp switch
- Multifunction switch
- Steering Column Control Module (SCCM)
- BCM (Body Control Module) (located in the RH kick panel)
The headlamp system is a dual-beam pattern system and consists of replaceable low/high beam bulbs.
The BCM (Body Control Module) supplies voltage to the headlamps when demanded. If the headlamps are on when the ignition switch is turned off, the battery saver feature turns off the headlamps after 10 minutes have elapsed.
Autolamps
The autolamp system consists of the following components:
- Headlamp switch
- Light sensor
- SCCM (Steering Column Control Module)
- BCM (Body Control Module)
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 (20 seconds is the factory default setting). The pre-selected time lapse is adjustable up to approximately 3 minutes. To change the autolamps time delay, refer to Autolamps Time Delay Adjustment .
Headlamps On With Wipers On Feature
When the headlamp switch is in the AUTOLAMPS ON position and the front wipers are on for more than 3 seconds (except during a mist wipe or while the wipers are on to clear washer fluid during a wash condition), the exterior lamps are turned on. The exterior lamps are turned off when the ignition switch is changed to the OFF or ACC position, the headlamp switch is placed in the OFF position, or the front wipers are off for more than 30 seconds. The exception to this is when the exterior lights are on because of darkness determined by the light sensor.
Stoplamps
The stoplamp system consists of the following components:
- Stoplamp switch
- High mounted stoplamp
- Rear lamps
- BCM (Body Control Module)
The stoplamp switch is located on the brake pedal assembly. The rear lamps and high mounted stoplamp are supplied voltage when the brake pedal is applied. The rear lamps are combination stop/turn lamps.
Turn Signal/Hazard Lamps
The turn signal and hazard lamp system consists of the following components:
- Front turn signal lamps
- Exterior mirror turn signal lamps
- Multifunction switch
- SCCM (Steering Column Control Module)
- BCM (Body Control Module)
When the multifunction switch is placed in the LH or RH TURN position, the BCM (Body Control Module) provides on/off voltage to the LH or RH turn signal lamps. The BCM (Body Control Module) cycles the voltage on and off approximately 80 times per minute. If a front or rear turn bulb is inoperative, the BCM (Body Control Module) cycles the voltage on and off approximately 160 times per minute.
The hazard switch is located on the top side of the steering column. When the hazard switch is pressed, the BCM (Body Control Module) cycles the voltage on and off approximately 80 times per minute.
The front turn signal indicator lamps are integrated into the headlamp assemblies.
The rear lamps share functionality with the stoplamps.
Parking Lamps
The parking lamp system consists of the following components:
- Headlamp switch
- Front and side marker lamps
- Cab marker lamps
- Exterior mirror lamps
- Rear and side marker lamps
- SCCM (Steering Column Control Module)
- BCM (Body Control Module)
The BCM (Body Control Module) supplies voltage to the parking lamps when demanded.
The front parking and side lamps are integrated into the headlamp assemblies.
The rear parking lamps are located in the rear lamp assemblies.
Vehicles equipped with dual rear wheels have marker lamps located on the sides and rear of the pickup bed. The vehicle can also come equipped with cab marker lamps located on the roof or marker lamps located on the trailer tow exterior mirrors.
Fog Lamps
The fog lamp system consists of the following components:
- Headlamp switch
- Fog lamps
- SCCM (Steering Column Control Module)
- BCM (Body Control Module)
The fog lamp switch is integrated into the headlamp switch. The fog lamps can be turned on when the ignition switch is in the RUN or ACC position, the parking lamps are on, and the high beam headlamps are off.
When the fog lamp switch is engaged, voltage is provided to the fog lamps.
Reversing Lamps
The reversing lamp system consists of the following components:
- Rear lamps
- Reversing lamp switch
- PCM
- BCM (Body Control Module)
When the transmission is placed in REVERSE (R), the BCM (Body Control Module) provides voltage to the reversing lamps. The reversing lamps are located within the rear lamp assemblies.
Trailer Tow
The trailer tow system consists of the following components:
- Trailer tow connector
- Trailer tow relays
- Trailer Brake Control (TBC) module
The Battery Junction Box (BJB) supplies voltage to the trailer tow stop/turn, parking and reversing lamps. When the vehicle's rear stop/turn, parking lamps or reversing are illuminated, voltage is also supplied to a corresponding trailer tow relay located in the BJB (Battery Junction Box).
The trailer tow battery charge relay provides voltage to the trailer tow connector when the ignition switch is in the RUN position.
The vehicle can be equipped with a factory manufactured TBC (Trailer Brake Control) module. For diagnostic information, refer to Trailer Brake Control Module.
On vehicles not equipped with a factory manufactured TBC (Trailer Brake Control) module, the vehicle comes equipped with circuitry to support an aftermarket TBC (Trailer Brake Control) module.
Daytime Running Lamps (DRL)
NOTE: The BCM (Body Control Module) can be configured to turn the Daytime Running Lamps (DRL) on for this vehicle. for programmable parameter information.
The DRL (Daytime Running Lamps) system utilizes the existing circuitry and components from the headlamp system.
The DRL (Daytime Running Lamps) system operates the low beam headlamps at a reduced intensity.
The BCM (Body Control Module) illuminates the low beam headlamps at a reduced intensity when the following conditions are met:
- The ignition switch is in the RUN position.
- The headlamps have not been turned on by the autolamp system or the headlamp switch.
- The transmission is not in PARK (P) (automatic transmission).
- The parking brake is not applied (manual transmission).