System Operation

Body Closures

System Operation

System Diagram





Network Message Chart

Module Network Input Messages - LTM (Liftgate/Trunk Module)






Power Open

The power liftgate power open operation begins when the LTM (Liftgate/Trunk Module) receives an input from one of the following:
- The LTM (Liftgate/Trunk Module) receives a momentary ground signal from the instrument panel power liftgate switch.
- The BCM (Body Control Module) receives a signal from the RKE (Remote Keyless Entry) transmitter (double button press).
- The LTM (Liftgate/Trunk Module) receives a signal from the BCM (Body Control Module) (without IA (Intelligent Access)) indicating the exterior liftgate handle has been activated.
- The LTM (Liftgate/Trunk Module) receives a MS-CAN (Medium Speed Controller Area Network) message from the RFA (Remote Function Actuator) module indicating an IA (Intelligent Access) request.

Once the LTM (Liftgate/Trunk Module) receives an open request, it opens the power liftgate by carrying out the following:
- The LTM (Liftgate/Trunk Module) checks the gear selector lever position and vehicle speed status from the MS-CAN (Medium Speed Controller Area Network).
- The LTM (Liftgate/Trunk Module) supplies power to the unlatch/cinching motor until the sector gear switches indicate end of travel, releasing the power liftgate latch.
- The power liftgate detent switch, primary forkbolt switch and secondary forkbolt switch circuits are monitored for correct latch release states.
- Power is supplied to the drive motor, opening the power liftgate.
- The LTM (Liftgate/Trunk Module) supplies power to the unlatch/cinching motor while monitoring the sector gear switches to return the sector gear to the neutral position.
- When the power liftgate is opening, the position sensor is monitored for liftgate position and velocity. If an obstruction is detected, the liftgate stops.
- If a second press of the instrument panel power liftgate switch or a double press of the RKE (Remote Keyless Entry) transmitter is detected, the liftgate stops.
- The power liftgate full open position is learned by the LTM (Liftgate/Trunk Module) during the power liftgate initialization. When the power liftgate reaches the full open position or a customer programmed open height, the LTM (Liftgate/Trunk Module) removes the power from the drive assembly actuator motor.
- After the power is removed from the drive motor, the position sensor briefly continues to monitor the position of the liftgate. If excessive movement in the closed direction is detected, power is reapplied to the motor and a continuous chime is initiated and remains on as the liftgate automatically closes.

Power Close

The power liftgate power close operation begins when the LTM (Liftgate/Trunk Module) receives an input from one of the following:
- The LTM (Liftgate/Trunk Module) receives a momentary ground signal from the instrument panel power liftgate switch.
- The LTM (Liftgate/Trunk Module) receives a momentary ground signal from the rear power liftgate switch.
- The BCM (Body Control Module) receives a signal from the RKE (Remote Keyless Entry) transmitter (double button press).

Once the LTM (Liftgate/Trunk Module) receives an close request, it closes the power liftgate by carrying out the following:
- The LTM (Liftgate/Trunk Module) checks the gear selector lever position and vehicle speed status from the MS-CAN (Medium Speed Controller Area Network).
- The LTM (Liftgate/Trunk Module) starts an audible chime.
- After 1 second of audible chime, power is supplied to the drive motor as the audible chime continues 3 seconds total.
- As the power liftgate is powered closed, the position sensor is monitored for liftgate position and velocity. The power liftgate reverses if an obstruction is detected.
- Also, as the power liftgate is powered closed, the pinch strips are monitored for a pinch condition. The power liftgate reverses if an obstruction is detected by either pinch strip.
- The power liftgate detent switch, primary forkbolt switch and secondary forkbolt switch circuits are monitored for correct latch states.
- The LTM (Liftgate/Trunk Module) receives switch states indicating the secondary latch position is reached, power is supplied to the unlatch/cinching motor to pull the liftgate into the primary latch position. When primary latch position is reached, power is removed from the drive motor.
- When the LTM (Liftgate/Trunk Module) receives switch states indicating the primary latch position has been reached (liftgate is fully closed), the LTM (Liftgate/Trunk Module) reverses the direction of the unlatch/cinching motor until the sector gear switches indicate the neutral position.

If any of the power liftgate switches or the button on the RKE (Remote Keyless Entry) transmitter is pressed during a power close, the liftgate stops and holds its position.

Liftgate Latch Manual Release

In the event of a failure with the power liftgate system, the liftgate can still be opened. REFER to Liftgate Latch Manual Release for additional information.