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The trunk release is controlled by an electronic control moduel .
Trunk Release Relay
The rear integration module grounds the trunk relay when commanded ON. The rear compartment should release.
This vehicle has a very complex body control system of three different computers
The body control system consists of the following 3 modules:
• The Dash Integration Module (DIM)
• The Instrument Panel Module (IPM)
• The Rear Integration Module (RIM)
Each of the 3 body control modules integrate a number of functional systems under the control of a single module. Each module is connected to the Class 2 serial data circuit, many of the control functions are implemented by Class 2 messages.
. Rear Integration Module (RIM)
The various RIM inputs and outputs are described in the corresponding functional areas as indicated on the RIM electrical schematics.
The RIM functions include the following:
• Automatic level control
• CIGAR relay control
• Class 2 communication requiring RIM interaction
• Content theft deterrent
• Fuel door control
• Fuel level sensor input
• Heated seat control
• HVAC blower control
• LK/CYL relay control
• Park brake relay control
• Rear defog relay control
• Rear park assist chime control
• Retained accessory power (RAP) relay control
• Reverse relay control
• Transmission shift inhibit
• Trunk release relay control
• Various controls for the interior lamps
Luggage Compartment Description and Operation (General)
Rear Compartment Lid (trunk) release actuation is controlled by the following components.
• Rear Compartment Lid Release Relay
• Instrument Panel Module (IPM)
• Rear Integration Module (RIM)
• Valet Switch
• Rear Compartment Lid Release Switch
• Rear Compartment Lid Release Actuator
Battery voltage for the coil side of the trunk release relay is supplied through the Valet switch (with the valet switch in the OFF position) by the ALDL fuse located in the Underhood Fuse (Bussed) Block. Battery voltage for the switch side of the trunk release relay is supplied by the Body fuse located in the Rear Fuse (Bussed) Block. When the rear compartment lid release switch is momentarily pressed, it provides a ground circuit for the trunk release signal of the Instrument Panel Module (IPM). When the IPM senses that the switch has been activated, it sends a Serial Data Class 2 message to the Rear Integration Module (RIM). The RIM then provides a path to ground on the F/TNK DR REL relay control circuit. The trunk release relay is then energized, and battery voltage is applied through the switch side contacts of the trunk release relay to the rear compartment lid release actuator. The actuator is connected to ground through a ground splice pack located at the left rear corner of the rear compartment, near the left tail lamp connector.