Courtesy Lamp: Description and Operation

Interior Lighting
The interior lighting is broken down in three groups: the courtesy lamps, the illuminated entry lamps and the illuminated exit lamps. All three lighting features interact with the courtesy light arbitrator. The battery saver is also listed. The brief descriptions are listed below.

Courtesy Lamps
The courtesy lamps consist of the dome lamp and map lamps and, optionally, exterior puddle lamps. The courtesy lamps can be activated by the Generic Electronic Module (GEM) using the panel dimmer switch, or by any ajar door. The courtesy lamps will shut off when the doors are closed and the illuminated entry feature is not active, the vehicle speed is greater than 15 mph and a new door open warning lamp switch signal is received.

The inputs are:
^ door ajar switches (from security interface receiver)
^ Vehicle Speed Sensor (VSS)
^ on-demand/dome lighting switch

The output is:
^ interior lamp relay

Illuminated entry
The illuminated entry feature requests the courtesy lamps be lit when the ignition switch is turned off and the customer activates an external unlock feature such as Remote Keyless Entry (RKE), keypad or key cylinder. The illuminated entry feature requests the courtesy lamps to extinguish when: 25 seconds expire, the ignition transitions out of OFF, or the customer activates an external lock feature.

The inputs are:
^ ignition switch position
^ illuminated entry request (from security interface receiver)

The output is:
^ interior lamp relay

Illuminated Exit
The illuminated exit feature requests the courtesy lamps be turned on for 25 seconds when all doors are closed and the ignition key is removed from the ignition cylinder. The illuminated exit feature will request the lamps be turned off when any door becomes ajar, the key is reinserted into the ignition cylinder, or the 25 seconds expire.

The inputs are:
^ key-in ignition switch
^ door ajar switches (from security interface receiver)

The output is:
^ interior lamp relay

Courtesy Lighting Arbitrator
The courtesy lighting arbitrator arbitrates between courtesy lighting, illuminated entry lighting, illuminated exit lighting, on-demand courtesy (dome lamp switch and interior lamp disable), and battery saver to determine which feature has precedence in turning on and off the courtesy lights. This feature is internal to the GEM module.

The inputs are:
^ battery saver request
^ courtesy lighting request
^ illuminated exit lighting request
^ illuminated entry request
^ on-demand/dome lighting switch

The output is:
^ interior lamp relay

Battery Saver
When the ignition is OFF or the key is out, the battery saver timer feature provides timed automatic shut-off of power to courtesy lamps, demand lamps and the warning chimes. The courtesy lamps interrupt has a time-out period of 10 minutes. The demand lamps and warning chime interrupt has a timeout period of 30 minutes.

The inputs are:
^ ignition switch position
^ door ajar warning (from security interface receiver)
^ key-in ignition switch
^ on-demand/dome lighting switch

The outputs are:
^ interior lamp relay
^ battery saver relay
^ warning chimes (internal to the GEM).