For 1990-2009 cars

### Rear Compartment Lid Release System Components

The rear compartment lid release system consists of the following components:

• | Body control module (BCM)

• | Folding top cover actuator

• | GMLAN serial data link

• | Keyless entry transmitter

• | Rear compartment lid ajar switch

• | Rear compartment lid release actuator

• | Rear compartment lid release switch

• | Remote control door lock receiver (RCDLR)

• | Trunk fuses

• | Trunk release relay

### Rear Compartment Lid Release System Operation

The rear compartment lid can be released by operating the rear compartment lid release switch or pressing the rear compartment lid release button on the keyless entry transmitter. When the rear compartment lid release switch is operated, the rear compartment lid release switch signal circuit to the body control module (BCM) is switched to ground. The BCM receives the rear compartment lid release switch input and applies ground to the trunk release relay control circuit. This energizes the trunk release relay coil, closing the switch side contacts, allowing battery voltage to be applied to the rear compartment lid release actuator and folding top cover actuator, releasing the buttresses and opening the rear compartment lid. Ground for the rear compartment lid release switch is provided at G300. The rear compartment lid ajar switch, rear compartment lid release actuator, and folding top cover actuator are provided ground at G301. The rear compartment lid will not release until the vehicle speed is zero and in park. For more detailed information concerning keyless entry refer to Keyless Entry System Description and Operation .

The rear compartment lid release actuator and folding top cover actuator are remotely located in the forward area of the rear compartment on the left side. The rear compartment lid release actuator activates the rear compartment latch release with the use of a cable. When activated, the rear compartment lid release actuator pulls the cable, releasing the rear compartment latch. The folding top actuator operates in a similar manner, except that the two folding top release motors both pull in series on a single cable which activates both left and right buttress release mechanisms.

### Trunk Ajar Indicator System Components

• | Body control module (BCM)

• | Driver information center (DIC)

• | GMLAN serial data link

• | Instrument panel cluster (IPC)

• | Rear compartment lid ajar switch

### Trunk Ajar Indicator System Operation

The trunk ajar indicator system function is to alert the vehicle operator when the vehicle's rear compartment lid has inadvertently been left ajar or open. Failure of the trunk ajar indicator system does not affect rear compartment lid operation or any other vehicle system.

The driver information center (DIC) located at the bottom of the instrument panel cluster (IPC), illuminates the TRUNK AJAR indicator when the body control module (BCM) detects that the rear compartment lid ajar switch is closed to ground indicating the rear compartment lid is open. The IPC receives a GMLAN serial data message from the BCM indicating the rear compartment lid ajar status. If this message is displayed and the vehicle speed is greater than 4.8 km/h (3 mph), a chime will sound.