Interior Lighting

INTERIOR LIGHTING
The Courtesy lights and illuminated entry feature are controlled by the Central Timer Module (CTM). The CTM will activate the courtesy lamps, including Map Lights and the Dome Lights when either the dome lamp switch is turned ON or a door is opened. The courtesy lamps will fade to OFF immediately when all doors are closed and the ignition is in the RUN or ACCY position.

The illuminated entry feature operates under the following conditions:
- RKE "unlock"
- Driver/Passenger door is opened
- Unlocking either the driver or passenger using the key (vehicles equipped with security system)
- The dome lamp switch is turned ON

Once activated, the illuminated entry will "fade to OFF" after 3 to 5 seconds under the following conditions: All doors are closed and:
- RKE "lock signal is received or
- Manual actuated power "lock" signal is received
or
- Ignition switch is turned to the ON position or
- 30 seconds have elapsed without any other action

Addition RKE unlock actuation before the expiration of illuminated entry will reset timer. Opening any door before the 30 second timer expires, will reset the entry time to 30 seconds and the illuminated entry timer will not begin counting down again until all doors are closed.

The Cargo lamps are controlled by the CTM. Placing the dome lamp switch in the cargo lamp position grounds an input to the CTM. The CTM then sends voltage to the cargo lamps. When an unlock button of the RKE is pressed, the cargo lights will turn ON for 30 seconds, similar to the illuminated entry feature.

The Interior lamp defeat feature will not allow any interior lamp to be turned ON. This is accomplished through an input to the CTM from the dome lamp switch.

The CTM provides battery protection by shutting down the interior lamps and cargo lights due to the following.

Leaving a door open, dome lamp switch ON, reading/ vanity lamp switch ON or glove box door open for more than 15 minutes while the ignition is OFF.

Door Ajar Switch
The door ajar state is used as an input for various control modules on the vehicle. The DRB III will display the state of the door ajar switches in Inputs/Outputs. It's important to note, that when a door is closed, the switch state of the DRB III will show OPEN, and when the door is open, the switch state will show CLOSED. During diagnosis, if a door is closed and the DRB III displays the switch state as CLOSED, it indicates a shorted door ajar circuit. If the door is open and the DRB III displays the switch state as OPEN, it indicates an open door ajar circuit.

The door ajar switches close a path to ground for the Central Timer Module (CTM) when a door is opened. The passenger side front door and both rear door ajar switches are connected in a parallel-series circuit between ground and the CTM, while the driver side front door ajar switch is connected in series between ground and the CTM to provide a unique input. The CTM reads the switch status through an internal pull-up, then sends the proper switch status messages to other electronic modules over the Programmable Communications Interface (PCI) data bus network. The door ajar switches can be diagnosed using conventional diagnostic tools and methods.

The door ajar switches are integral to the door latches on each door The switches close a path to ground for the Central Timer Module (CTM) when a door is opened.

The door ajar switches cannot be repaired and, if faulty or damaged, the door latch unit must be replaced.