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Courtesy Lamp: Description and Operation

COURTESY/ILLUMINATED ENTRY LAMPS
When the Body Control Module (BCM) is in an active state (awake) it energizes the courtesy lamps supply voltage circuit. The courtesy lamps supply voltage circuit supplies voltage to all of the interior lamps, including the illuminated entry lamps (courtesy lamps). The illuminated entry lamps are turned on when they receive a ground from the courtesy lamp low control circuit of the BCM. When the ignition is in the LOCK position the BCM will ground the courtesy lamp low control circuit under the following conditions:
- The door jamb input transitions to an active state (opening a door).
- The use of the remote keyless entry (RKE) to unlock the side doors.

When the courtesy lamps supply voltage circuit and the courtesy lamp low control circuit are active the courtesy/illuminated entry lamps will illuminate. The courtesy lamps/illuminated entry lamps include the following interior lamps :
- The dome lamp
- The roof rail courtesy lamps
- The I/P courtesy lamps
- The inside rear view mirror

When the driver uses the remote function actuator transmitter to unlock the doors, the BCM will illuminate the courtesy lamps for approximately 40 seconds, unless another BCM function causes the lamps to remain active. If the ignition switch is turned to either the RUN or START position the courtesy lamps will turn off immediately.

When the door latch switch signal circuit is active with the ignition in the OFF position the BCM will illuminate the courtesy lamps. The courtesy lamps will remain illuminated for approximately 25 seconds, after the door latch switch signal circuit becomes inactive, unless another BCM function causes the lamps to remain active. If the ignition switch is turned to either the RUN or START position the courtesy lamps will turn off immediately.

COURTESY/ILLUMINATED EXIT
The illuminated exit feature will activate the courtesy lamps when the key IN input of the BCM transitions from an active state to an inactive state (removing the ignition key). When the key is removed from the ignition, the key IN input to the BCM becomes inactive. The BCM will illuminate the courtesy lamps for approximately 25 seconds, unless another BCM function causes the lamps to remain active.

COURTESY LAMPS MANUAL OPERATION
The courtesy lamps, may be manually operated by the IP dimmer switch. When the IP dimmer switch is placed in the ON position the BCM receives a ground from the courtesy lamp switch signal circuit. Upon receiving the courtesy lamp switch signal the BCM then pulls low the courtesy lamp low control output circuit, which illuminates the courtesy lamps. The voltage for all interior lamps is supplied by the courtesy lamp supply voltage circuit of the BCM, whenever the BCM is active. The interior lamp switch will override any BCM operation of the interior lamps, such as entry illumination.

IP COURTESY LAMP
The IP courtesy lamp is turned ON by the IP dimmer switch or during illuminated entry.

During illuminated entry or when the IP dimmer switch is ON the BCM wakes up and then energizes the courtesy lamps supply voltage circuit, suppling voltage to all interior lamps. The BCM pulls the courtesy lamp low control circuit low, providing ground to the IP courtesy lamps and all courtesy lamps.