Courtesy Lamps
The BCM controls the courtesy lighting functions and timing by monitoring inputs from the following:
- Door ajar switches
- Liftgate ajar switch (if equipped)
- Ignition state
- RKE system
The BCM sends a voltage signal to each door or liftgate ajar switch. When the doors or liftgate are closed, the circuit is switched to ground and the voltage is pulled low, indicating closed doors.
For vehicles equipped with door modules, the DDM and the PDM provides ground for the door ajar switch.
The BCM monitors the ignition state and inputs from the RKE system to determine when to energize the interior light relay. When the interior light relay is energized, voltage is provided to the interior lamps. The BCM controls the ground side of the courtesy lamps for the illuminated entry and exit features.
For remote keyless entry, the BCM monitors input from the Integrated Keyhead Transmitters (IKTs) to determine when to activate/deactivate the illuminated entry and exit functions.
The interior courtesy lamps can also be activated from the courtesy lamp switch mounted on the front/ driver interior lamp. The front interior lamp (vehicles without a roof opening panel) or the driver interior lamp (vehicles with a roof opening panel) controls the courtesy lamp function of the remaining interior lamp(s). When the courtesy lamp button is pressed on the front/driver interior lamp, the courtesy lamp function for all the lamps is turned on/off. If any door is open, the BCM command overrides the function of the front/driver courtesy lamp switch and activates the courtesy lamps.