Part 4

Position Lamps - European

The position lamps are on export vehicles only. European countries require that side position lamps are activated when the vehicle is parked along the side of the road. This feature utilizes the front and rear park and the side marker lamps. The position lamp function operates only when the key is in the OFF position and the gear selector is in the PARK position. The position lamp function will operate when the turn signal switch is placed in the right turn position for the right side position lamps to illuminate or the left turn position for the left side position lamps to illuminate. Battery positive voltage is supplied to the standing lamp relay coil and switch. Battery positive voltage is supplied through the normally closed relay contacts of the standing lamp relay switch to each position lamp relay coil. Battery positive voltage is supplied to each position lamp relay switch. When the driver places the turn signal lever in the right or left turn position, the turn signal switch grounds the respective position lamp relay control circuit. This energizes the relay coil, closing the switch contacts providing battery voltage to the respective park and side marker lamps. When the gear selector is out of the PARK position, the rear integration module (RIM) grounds the standing lamp relay coil which removes battery positive voltage from each position lamp relay coil.

Stop Lamps

The brake pedal position (BPP) sensor is used to sense the action of the driver application of the brake pedal. The BPP sensor provides an analog voltage signal that will increase as the brake pedal is applied. The instrument panel module (IPM) provides a low reference signal and a 5-volt reference voltage to the BPP sensor. When the variable signal reaches a voltage threshold indicating the brakes have been applied, the IPM will apply battery voltage to the center high mounted stop lamp (CHMSL), transmission control module (TCM), engine control module (ECM), and stop lamp relay. When the stop lamp relay receives battery voltage from the IPM, the relay coil is energized and the stop lamp relay switch contacts close applying battery voltage through the stop lamps fuse to illuminate the stop lamps. The stop lamps consist of red lenses and light emitting diodes (LED) instead of incandescent bulbs. The stop lamps on this vehicle will not illuminate unless the ignition is in the accessory, run, or crank positions. When the ignition is in the OFF position, the stop lamps will not illuminate when the brake pedal is applied.

Turn Signal Lamps

With the ignition switch in the RUN position, the turn signal lamps will illuminate when the driver places the turn signal switch in the right or left positions. The instrument panel module (IPM) monitors the signal circuit of the turn signal/multifunction switch. The IPM relays the turn signal switch status to the rear integration module (RIM) via the serial data circuit. The RIM uses the status of the turn signal switch to command the turn signals ON and OFF. The RIM controls both front and rear turn signals. The IPM also sends a message via GMLAN to the instrument panel cluster (IPC) to enable the turn signal indicators located in the IPC ON and OFF depending on the position of the turn signal switch. Voltage is supplied to the front and rear turn signals by the RIM. The rear turn signal functions are performed by the quarter mounted tail lamps. The rear turn signal lamps consist of red lenses and light emitting diodes (LED) instead of incandescent bulbs.

Hazard Flasher Lamps

The hazard flashers may be activated in any power mode. The instrument panel module (IPM) monitors the signal circuit of the hazard switch. When the hazard switch is placed in the ON position, the switch contacts close and battery positive voltage from the IPM flows through the hazard switch to ground. The rear integration module (RIM) turn lamp supply voltage circuit is also provided with ground through the hazard switch when the contacts close at ground which in turn illuminates the hazard switch LED. The RIM uses the status of the hazard switch to command the turn signals ON and OFF. The RIM controls both front and rear turn signals. The IPM sends a message via GMLAN to the instrument panel cluster (IPC) to enable both turn signal indicators in an ON and OFF duty cycle when the hazard switch is placed in the ON position. Voltage is supplied to the front and rear turn signals by the RIM.

Repeater Lamps

The repeater lamps are located on the side of the front fender. The repeater lamps are used as additional turn signal lamps, and operate as described in the Turn Signal Lamps description. The repeater lamps are hard wired to their respective front turn signals.

Backup Lamps

The left rear fuse block supplies battery positive voltage through the REVERSE LAMP fuse to the coil and switch terminals of the reverse lamp relay. The instrument panel module (IPM) sends a power mode message to the rear integration module (RIM) indicating that the ignition is in the RUN position. When the driver places the gear selector in the REVERSE position, the powertrain control module (PCM) sends a message via serial data to the RIM. The RIM provides ground to the reverse lamp relay control circuit which energizes the reverse lamp relay coil. With the reverse lamp relay coil energized, the relay switch contacts close and allow battery positive voltage to flow from the REVERSE LAMP fuse through the relay switch to illuminate the backup lamps.

Battery Run Down Protection/Inadvertent Power

To provide battery run down protection, the exterior lamps will be deactivated automatically under certain conditions. The instrument panel module (IPM) monitors the state of the turn signal/multifunction switch. If the park or headlamp switch is ON when the ignition switch is placed in either the CRANK or RUN position and then placed in the OFF position, the IPM initiates a 10-minute timer. At the end of the 10 minutes, the IPM will turn OFF the control power output to the park and headlamp relay coils, deactivating the exterior lamps. This feature will be cancelled if any power mode other than OFF becomes active. The IPM will disable battery run down protection if any of the following conditions exist. The park or headlamp switch is placed in the ON to OFF position, and back to the ON position during battery run down protection. The IPM determined that the park or headlamp switch was not active when the ignition was turned OFF.