Diagnostic Routine B
Diagnostic Routine B
Diagnostic Overview
The Power Liftgate Is Inoperative from An Individual Switch
Refer to Wiring Diagram Set 109 for schematic and connector information Electrical Diagrams.
Normal Operations and Fault Conditions
The LTM (Liftgate/Trunk Module) receives inputs from the instrument panel and rear power liftgate open/close switches. The LTM (Liftgate/Trunk Module) sends a voltage signal to the switches on the input circuits. When either switch is pressed, the corresponding voltage signal is connected to ground signaling the LTM (Liftgate/Trunk Module) to open or close the liftgate. Both switches are connected to ground.
The LTM (Liftgate/Trunk Module) also receives a signal from the BCM (Body Control Module) (without IA (Intelligent Access)) or RFA (Remote Function Actuator) module (with IA (Intelligent Access)) when the exterior liftgate release switch or a RKE (Remote Keyless Entry) transmitter button is pressed and conditions allow the liftgate to open. For vehicles without IA (Intelligent Access), the BCM (Body Control Module) sends the LTM (Liftgate/Trunk Module) a voltage signal on a liftgate open/close request circuit. For vehicles without IA (Intelligent Access), the RFA (Remote Function Actuator) module sends the open/close request to the LTM (Liftgate/Trunk Module) over the MS-CAN (Medium Speed Controller Area Network).
DTC Fault Trigger Conditions
Visual Inspection and Diagnostic Pre-checks
- Power liftgate switch - instrument panel
- Power liftgate switch - rear
- Power liftgate switch - exterior
Pinpoint Test
1. CHECK THE OPERATION OF THE POWER LIFTGATE SWITCHES
1. NOTE: Make sure the power liftgate is on (enabled) in the message center.
Close the liftgate to the full closed position (manually, if necessary).
2. Electronically unlock the vehicle.
3. Activate the power liftgate from the power liftgate control switch (instrument panel).
4. Activate the power liftgate from an RKE (Remote Keyless Entry) transmitter.
5. Activate the power liftgate from the liftgate exterior switch.
6. With the liftgate in the open position, activate the power liftgate from the power liftgate rear control switch.
Does the power liftgate open/close from at least one switch?
2. RETRIEVE THE DTCs (Diagnostic Trouble Codes) FROM THE LTM (Liftgate/Trunk Module)
1. Using a scan tool, perform the LTM (Liftgate/Trunk Module) self-test.
Is DTC (Diagnostic Trouble Code) B1105 or B2703 present?
3. CHECK THE POWER LIFTGATE SWITCHES FOR A SHORT TO GROUND
1. Disconnect: Power Liftgate Control Switch C2114 (for DTC (Diagnostic Trouble Code) B2703).
2. Disconnect: Power Liftgate Rear Control Switch C4333 (for DTC (Diagnostic Trouble Code) B1105).
3. Using a scan tool, clear the LTM (Liftgate/Trunk Module) DTCs (Diagnostic Trouble Codes).
4. Using a scan tool, perform the LTM (Liftgate/Trunk Module) self-test.
Is DTC (Diagnostic Trouble Code) B1105 or B2703 retrieved?
4. CHECK THE LTM (Liftgate/Trunk Module) CONTROL SWITCH INPUTS FOR A SHORT TO GROUND
1. Ignition OFF.
2. Disconnect: LTM (Liftgate/Trunk Module) C4174B.
3. For DTC (Diagnostic Trouble Code) B1105, measure:
4. For DTC (Diagnostic Trouble Code) B2703, measure:
Is the resistance greater than 10,000 ohms?
5. CHECK POWER LIFTGATE REAR SWITCH CIRCUIT OPERATION
1. Disconnect: Power Liftgate Control Switch C2114 (for an inoperative front switch).
2. Disconnect: Power Liftgate Rear Control Switch C4333 (for an inoperative rear switch).
3. For an inoperative rear switch, connect a fused jumper wire:
4. For an inoperative front switch, connect a fused jumper wire:
Does the power liftgate open or close?
6. CHECK THE SWITCH GROUND CIRCUIT FOR AN OPEN
1. For an inoperative rear switch, connect a fused jumper wire:
2. For an inoperative front switch, connect a fused jumper wire:
Does the power liftgate open or close?
7. CHECK THE SWITCH INPUT CIRCUIT FOR AN OPEN
1. Ignition OFF.
2. Disconnect: LTM (Liftgate/Trunk Module) C4174B.
3. For an inoperative rear switch, measure:
4. For an inoperative front switch, measure:
Is the resistance less than 3 ohms?
8. CHECK FOR CORRECT LTM (Liftgate/Trunk Module) OPERATION
1. Ignition OFF.
2. Disconnect and inspect all LTM (Liftgate/Trunk Module) connectors.
3. Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
4. Reconnect all the LTM (Liftgate/Trunk Module) connectors. Make sure they seat and latch correctly.
5. Operate the system and determine if the concern is still present.
Is the concern still present?
