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For 1990-2009 cars only

Interior Lamps

The interior lamps consists of two groups, lamps that can not be dimmed and lamps that can be dimmed. This first group consists of lamps that may not be dimmed. This includes those lamps that may be manually turned on by placing the interior lamp switch to the DOME position, or by opening a door or a compartment:

    • Door courtesy lamps
    • Footwell courtesy lamps
    • Instrument panel (I/P) compartment lamp
    • Overhead console courtesy lamps
    • Reading courtesy lamps
    • Rear compartment courtesy lamp
    • Roof rail courtesy lamps
    • Sunshade vanity mirror lamps

Battery positive voltage is applied at all times to the INT LP fuse and to the coil side of the INT LAMP relay in the rear fuse block. The rear integration module (RIM) supplies a ground through the INT lamp control circuit to the INT LAMP relay coil. This energizes the INT LAMP relay and applies battery positive voltage to splice pack SP310 and splice pack SP306. From SP310 battery positive voltage is applied to:

    • I/P compartment lamp
    • RH footwell courtesy lamp
    • RH front door courtesy lamp
    • RH rear door courtesy lamp
    • Rear integrating module

From SP306 battery positive voltage is applied to:

    • LH and RH rear roof rail courtesy lamps
    • LH front door courtesy lamp
    • LH front footwell courtesy lamp
    • LH rear door courtesy lamp
    • Overhead console reading courtesy lamps
    • Rear compartment courtesy lamp
    • Rear reading courtesy lamps
    • Sunshade vanity mirror lamps

The RIM activates the interior lighting output 15 seconds after receiving the class 2 message "Airbags Deployed" from the sensing and diagnostic module (SDM). The interior lamps then remain activated for 25 minutes.

Interior Lamp Operation

The interior lamps can be turned on three different ways:

    • By the headlamp lamp switch in the DOME position
    • By opening a door, if a low light condition exist
    • By unlocking the doors with the key FOB, if a low light condition exist

The courtesy lamps will normally turn off using the theater dimming feature. The rear integration module (RIM) provides a ground to all courtesy/reading, dome, and inside rear view mirror lamps for the theater dimming feature. The RIM will immediately turn off the courtesy lamps if a door lock command is received with all the doors closed, or if the ignition switch is turned to either the ON or RUN position. The courtesy lamps will remain on for approximately 40 seconds after the last door is closed. The RIM keeps the courtesy lamps on for approximately 40 seconds after an alarm event is completed.

Headlamp Switch

When the headlamp switch is placed in the DOME position, the instrument panel module (IPM) receives a ground signal from the headlamp switch. The IPM then applies a signal message through the class 2 communication to the rear integration module (RIM). The RIM then applies a ground to the INT lamp relay control circuit. This energizes the INT LAMP relay allowing battery positive voltage to be applied to all courtesy lamps. The RIM then applies a ground to the interior lamps ground control circuit to all the courtesy lamps, illuminating them.

Door Activated Courtesy Lamps

If the sunload sensor detects a low light condition, the rear integration module (RIM) applies a class 2 message to the rear integration module (RIM) indicating a low light level. When the LH front door is opened, the door lock actuator contacts close and the driver door module (DDM) receives a door-open /door-closed signal. The DDM then applies a class 2 message to the RIM. When the RIM receives a door lock or unlock input signal, the RIM will activate the INT LAMP relay, which provides battery positive voltage to all interior courtesy lamps. The RIM then applies a ground to the interior lamp ground control circuit illuminating the all courtesy lamps. After all the doors are closed, the courtesy lamps remain illuminated for approximately 25 seconds. The courtesy lamps will also turn on and remain illuminated for approximately 15 seconds after the ignition key is removed, prior to any door being opened.

When a passenger door is opened and the RIM has received a low light message, the door lock actuator contacts close and the corresponding door module receives a door-open signal. The door module then communicates through the Simple Bus Interface (SBI) to the DDM. The DDM then applies a class 2 message to the RIM. When the RIM receives a door lock the RIM will activate the INT LAMP relay, which provides battery positive voltage to all interior courtesy lamps. The RIM then applies a ground to the interior lamp ground control circuit illuminating the all courtesy lamp.

Keyless Entry Interior Illumination

When the remote function actuation (RFA) module receives a door unlock command from the key FOB, the RFA module applies a class 2 message to the rear integration module (RIM). If the RIM has received a low light message from the instrument panel module (IPM) and the following conditions are met:

    • All the doors are closed
    • The courtesy lamp switch is in the OFF position
    • The ignition switch is in the OFF position

Then the RIM will activate the INT LAMP relay, which provides battery positive voltage to all interior courtesy lamps. The RIM then applies a ground to the interior lamp ground control circuit illuminating the all courtesy lamp.

I/P Compartment Lamp

The INT LAMP relay provides battery positive voltage to the instrument panel (I/P) compartment lamp. When the I/P compartment is opened, a switch closes, providing a ground circuit to G201, and the I/P compartment lamp illuminates.

Reading Courtesy Lamps

The INT LAMP relay provides battery positive voltage to each of the reading courtesy lamps. When the switch is closed on the reading lamp, this provides a ground circuit to G402, and the reading lamp illuminates.

Rear Compartment Lamp

The INT LAMP relay provides battery positive voltage to the rear compartment lamp. When the rear compartment is opened, the rear compartment lid release actuator closes. Ground is applied from G401 through the rear compartment lid release actuator to the rear integration module (RIM). The RIM applies a ground through the rear compartment lid release actuator to the rear compartment lamp courtesy lamp, and the rear compartment lamp illuminates.

Sunshade Vanity Lamps

The INT LAMP relay provides battery positive voltage to each of the vanity mirror lamps. When the vanity mirror cover on the sunshade is opened, a switch closes in the cover, providing a ground circuit to G402, illuminating the vanity mirror lamps.

Battery Rundown Protection

Battery positive voltage is applied at all times to the INT LP fuse and to the coil side of the INT LAMP relay in the rear fuse block. The rear integration module (RIM) supplies a ground through the INT lamp control circuit to the INT LAMP relay coil. This energizes the INT LAMP relay and applies battery positive voltage to all the interior lamps. This relay provides a parasitic load protection and the RIM will keep this relay active for 10 minutes following the ignition being turned to the OFF position and retained accessory power (RAP) being deactivated or timed out. The 10 minutes is reduced to 3 minutes if mileage of the vehicle is less then 22.5 km (14 mi).