Exterior Lighting

EXTERIOR LIGHTING

NOTE: The smart junction box (SJB) must be reconfigured before installing a new module. Refer to Information Bus (Module Communications Network).

The SJB controls the front and rear portion of the vehicle. This system relies on the standard corporate protocol (SCP) communication network in order to transmit and receive signals. It is very important to understand:
- where the input (command) originates from.
- all information (messages) necessary in order for a feature to operate.
- which module(s) receive(s) the input or command message.
- if the module which received the input (message) controls the output of the feature, or does it output a message over the SCP communication network to another module.
- which module controls the output of the feature.

Exterior Lighting
The exterior lighting outputs are controlled by the SJB. An additional function of the lighting system is a lamp outage function which indicates to the driver if certain exterior bulbs are not functioning. If there is an inoperative bulb, the SJB sends a message to the instrument cluster and message center (if equipped), indicating that the lamp is inoperative.

Headlamps
The headlamps are controlled by the SJB. The headlamp and multifunction switches are hard-wired to the SJB and are constantly monitored. The SJB processes information (such as low beam, high beam or flash-to-pass requests) from these switches and outputs the appropriate command to the headlamps (which are also hard-wired to the SJB). This is the same for the low and high beams and flash-to-pass positions. The SJB provides a lamp outage indication for the low beams. Fault management of the headlamps provides some headlamp functionality. In the event of all multifunction switch, all headlamp switch or ignition switch invalid or missing data failures, the exterior lamps will be illuminated. There is also a headlamp battery saver feature. This feature turns off the headlamps ten minutes after the ignition switch is turned OFF.

Autolamps and DRL are two functions which may be configured in the SJB.

Autolamps
The autolamps are controlled by the headlamp switch, light sensor and the SJB. When the headlamp switch is in the autolamp position, the SJB monitors input from the photocell sensor. The SJB processes this information and outputs the appropriate command to the exterior lamps. The exterior lamps are hard-wired to the SJB. The autolamps remain ON for a preselected amount of time (approximately 20 seconds to three minutes depending on customer preferences) after the ignition switch is changed from the ON position to the ACC or OFF position.

The exit time delay is programmed in the following sequence.

NOTE: Steps 2 through 5 must be carried out within a 10-second period.

1. Make sure the ignition switch is turned OFF and the headlamp switch is in the autolamps ON position.
2. Place the headlamp switch to the OFF position.
3. Turn the ignition switch to the RUN position.
4. Turn the ignition switch to the OFF position.
5. Place the headlamp switch to the autolamps ON position (at this time the headlamps and parking lamps illuminate).
6. When the desired length of time is reached (maximum of 3 minutes), place the headlamp switch to the OFF position.

Turn Signal, Cornering and Hazard Lamps
All turn signal, cornering lamps, and signal mirror outputs are controlled by the SJB. The multifunction switch and the hazard switch are hard-wired to the SJB. When the multifunction switch is in the left or right turn position, or the hazard switch is engaged, the SJB processes this information and outputs the appropriate command to the turn signal and hazard lamps. All turn signal lamps provide a lamp outage indication.

Parking, Rear or License Lamps
All parking , rear license and marker lamps are controlled by the SJB. The headlamp switch is hard-wired to the SJB. When the headlamp switch is in the headlamps ON or parking lamps ON position, SJB processes this information and outputs the appropriate command to the parking or license lamps, which are hard-wired to the SJB. Only the left and right rear lamps provide lamp outage indication. Fault management of the parking lamps provides rear parking lamp functionality in the event of certain multifunction switch, headlamp switch, ignition switch or SJB failures.

Fog Lamps
The fog lamps are controlled by the headlamp switch. The switch toggles the fog lamps between on and off. When activated, the switch sends a signal to the SJB. The SJB then activates the fog lamp relay, providing power to the fog lamps. The fog lamps will not illuminate when the high beam headlamps are on.

Reversing Lamps
The reversing lamps are controlled by the SJB and the powertrain control module (PCM). The PCM sends a message through the SCP communication network to the SJB indicating the transmission is in REVERSE. The SJB processes this information and outputs the command to the reversing lamps which are hard-wired to the SJB.

Daytime Running Lamps (DRL)
If the SJB is configured for daytime running lamps (DRL), this feature illuminates the low beam headlamps at a reduced intensity when the following conditions exist:
- the ignition switch is in the RUN position
- the headlamp switch is in the OFF position
- the autolamps feature has not illuminated the exterior lamps
- the transmission is in DRIVE