System Operation
System Diagram
*.sttxt { visibility: hidden; } *.stcallout { visibility: visible; } E343684 1 RGTM 2 SYNC Display unit- Soft touch on the touchscreen switch 3 Exterior Liftgate Release Switch 4 Anti-Pinch Switches 5 BCM 6 Power Liftgate Motor 7 Power Liftgate Motor 8 Power Liftgate Hands Free Actuation Module 9 Power Liftgate Hands Free Actuation Sensors 10 Rear Interior Power Liftgate Switch 11 GWM 12 APIM 13 GWM 14 ACM 15 Motor 16 Position Sensor 17 Cinch Motor 18 Release Motor 19 Latch/Cinch SwitchesItem | Description |
---|---|
1 | RGTM |
3 | Exterior Liftgate Release Switch |
4 | Anti-Pinch Switches |
5 | BCM |
6 | Power Liftgate Motor |
7 | Power Liftgate Motor |
8 | Power Liftgate Hands Free Actuation Module |
9 | Power Liftgate Hands Free Actuation Sensor |
10 | Rear Interior Power Liftgate Switch |
11 | GWM |
12 | APIM |
13 | GWM |
14 | ACM |
15 | Motor |
16 | Position Sensor |
17 | Cinch Motor |
18 | Release Motor |
19 | Latch/Cinch Switches |
Network Message Chart
RGTM Network Input Messages
Broadcast Message | Originating Module | Message Purpose |
---|---|---|
Liftgate request | BCM | Used by the RGTM to open/close the liftgate when the BCM receives a valid request from a programmed RKE transmitter or the passive entry feature. |
Gear lever position | PCM | Used by the RGTM to inhibit power liftgate operation if the transmission is not in PARK. |
Power liftgate mode command | APIM | Used by the RGTM to enable/disable the power liftgate operation from both rear power liftgate switches. |
Vehicle lock status | BCM | Used by the RGTM to inhibit the power liftgate operation when the liftgate release switch is activated, unless the doors have been previously unlocked electronically. |
Power Liftgate
Power Open
The power liftgate power open operation begins when:
Once the RGTM receives an open request, the power liftgate opens by carrying out the following:
If any of the power liftgate switches is activated, a request for the hands-free feature is detected or a double press of the button on a RKE transmitter occurs during a power open, the liftgate stops and holds its position.
Power Close
The power liftgate power close operation begins when:
Once the close request is received, the power liftgate closes by carrying out the following:
If any of the power liftgate switches is activated, a request for the hands-free feature is detected or the button on the RKE transmitter is double pressed during a power close, the liftgate stops and holds its position.
NOTE: The power liftgate may not operate correctly under the following conditions:
If any of these conditions have occurred, the power liftgate must be re-initialized.
Power Liftgate Open Height Programming
The power liftgate open height can be programmed to open to a height other than the full open position. To program the power liftgate open height:
The programmed power liftgate height is retained when the battery is disconnected.
Power Liftgate Chime
The power liftgate chime provides audible warnings to the operator. The power liftgate chime is sounded using the audio system. The RGTM sends messages over the CAN to the ACM when requesting the chime to sound.
Power Liftgate Hands-Free Feature (if equipped)
In addition to the passive entry system, the power liftgate hands-free feature utilizes a module and 2 capacitive sensors (located behind the rear bumper cover) for operation. The BCM sends a voltage signal to the hands-free liftgate actuation module. The hands-free liftgate actuation module monitors the 2 sensors. When the correct motion is detected (forward and back such as a kicking motion under the rear bumper), the hands-free liftgate actuation module communicates to the BCM via a LIN . The LIN supports bi-directional communication between the hands-free liftgate actuation module and BCM , allowing the liftgate passive entry process to begin (as though the liftgate release button was pressed)
Hands-free liftgate DTC is set in the BCM , if any failure occurs over the LIN .
The BCM verifies a valid programmed passive key is within range of the rear keyless entry antenna and sends a message to the RGTM to open the liftgate.
For detailed information on the liftgate passive entry feature,
Refer
to: Handles, Locks, Latches and Entry Systems - System Operation and
Component Description (501-14 Handles, Locks, Latches and Entry Systems,
Description and Operation).
Component Description
Rear Interior Power Liftgate Switch
The rear interior power liftgate switch (located on the bottom of the liftgate trim panel) is a momentary contact switch that routes the voltage signal from the RGTM to ground when pressed. Pressing this switch closes the power liftgate. The power liftgate does not open or release the latch from the rear interior power liftgate switch.
Rear Exterior Liftgate Release Switch
The rear exterior liftgate release switch is a momentary contact switch that routes the voltage signal to ground when pressed. The signal is sent from the BCM and the RGTM .
If the doors were not previously electronically unlocked when the rear exterior liftgate release switch is pressed, the BCM activates the liftgate passive entry feature. If the BCM detects a valid programmed passive key, the BCM sends a message to the RGTM to open the liftgate. If no passive key is detected, the request is ignored.
If the doors were previously electronically unlocked when the liftgate switch is pressed, the RGTM opens the liftgate. The RGTM receives the door lock/unlock status from the BCM over the CAN .
Any subsequent presses of the switch stops the motion or reverses direction.
Power Liftgate Latch
The power liftgate latch is responsible for unlatching, latching and cinching the liftgate. The power liftgate latch contains an unlatch motor, a cinching motor, a pawl switch, forkbolt primary and secondary switches, and a sector gear switch.
Unlatch Motor
The unlatch motor is only driven in one direction to unlatch the liftgate, similar to an actuator activating. A spring returns the unlatch motor to a rest position.
Cinching Motor
The cinching motor is driven in one direction to cinch the liftgate and in the opposite direction to its start position.
During a cinch operation, power is supplied to the cinching motor by the RGTM when the secondary latch position is reached during a power close operation. When the motor activates, it pulls the liftgate into the primary latch position. When the fully latched position is reached, the RGTM reverses the polarity to the cinching motor until it reaches its start position.
Pawl Switch, Forkbolt Primary and Secondary Switches
The pawl, forkbolt primary and secondary switches provide input to the RGTM to determine the liftgate latch position. The liftgate is in the primary position when the liftgate is in the full closed position. The liftgate is in the unlatched position when the liftgate is open and completely out of the striker. The RGTM receives input from the power liftgate pawl, forkbolt primary and secondary switches in the following manner:
Latch Switch States
Latch Position | Forkbolt Primary Switch | Forkbolt Secondary Switch | Liftgate Pawl Switch |
---|---|---|---|
Fully Unlatched | Active | Active | Active |
Secondary | Inactive | Active | Inactive |
Primary | Inactive | Inactive | Inactive |
Sector Gear Switch
The sector gear switch opens and closes to provide input to the RGTM to determine the position of the cinching motor sector gear. During a cinching operation, the RGTM deactivates the cinching motor once the latch is detected as being in the primary latch position. The RGTM then reverses the direction of the cinching motor until the sector gear switch indicates the sector gear has returned to the start position.
Power Liftgate Motor
The power liftgate motors raises and lowers the liftgate. The power liftgate motors is bi-directional and contains a position sensor that provides input to the RGTM for liftgate position and velocity.
Position Sensor
The RGTM provides power and ground to the hall-effect sensors within the position sensor. It also supplies voltage signals to the position sensor on a valid open command or when the liftgate is in the open position. The position sensor has 2 data lines the RGTM monitors to determine liftgate movement and position. The RGTM uses the liftgate position information to determine which direction to power the liftgate (open or close) when a valid operation command is received. The movement is monitored to identify obstructions.
Anti-Pinch Switch
The liftgate anti-pinch switches are membrane-style switches. When the liftgate anti-pinch switch is compressed, the resistance change indicates to the RGTM an obstacle is present and prevents the liftgate from closing.
When the liftgate anti-pinch switch is not compressed, it has an approximate resistance of 5,700–6,700 ohms. When the liftgate anti-pinch switch is compressed, it has an approximate resistance of 0–200 ohms.
Hands-Free Liftgate Actuation Module
The hands-free liftgate actuation module is located behind the rear bumper cover on the right side of the vehicle. The hands-free liftgate actuation module receives a 12-volt signal from the BCM while monitoring 2 capacitive sensors. When the correct motion is detected from the upper and lower sensors, the hands-free liftgate actuation module communicates to the BCM via a LIN .
Hands-Free Liftgate Actuation Sensors
The hands-free liftgate actuation sensors are capacitive sensors and generate capacitive fields near the rear bumper. The capacitive fields are disrupted when an object (such as a leg) enters the area. The hands-free liftgate actuation module uses this information to interpret movement near the rear bumper.
RGTM
The RGTM sends voltage signals to the front and rear interior power liftgate switches and the exterior liftgate release switch. The signal is routed to ground when a switch is pressed, pulling the signal low to indicate a request to open or close the liftgate.
The RGTM receives a message from the BCM upon a valid request from the passive entry system or a RKE transmitter.
The RGTM controls the opening and closing of the power liftgate based on the inputs it receives.
The RGTM requires PMI when it is replaced.
WARNING: Always ride and drive with your seatback upright and properly fasten your seatbelt. Fit the lap portion of the seatbelt snugly and low across the hips. Position the shoulder portion of the seatbelt across your chest. Pregnant women must follow this practice. See the following figure.