Pinpoint Test A: Power Liftgate Is Inoperative - Does Not Open Or Close
Power Liftgate
Pinpoint Test A: The Power Liftgate is Inoperative - Does Not Open or Close
Normal Operation
The Liftgate/Trunk Module (LTM) receives battery voltage at all times through the Body Control Module (BCM) fuse 9 (10A) and Battery Junction Box (BJB) fuse 7 (30A). The LTM (Liftgate/Trunk Module) has a dedicated ground circuit.
During power opening and/or power closing operation, the LTM (Liftgate/Trunk Module) receives inputs from the following system components:
- Power liftgate control switch (instrument panel), power liftgate rear control switch (LH rear quarter trim panel), exterior liftgate switch or a Remote Keyless Entry (RKE) transmitter
- Pinch strips
- Power liftgate motor position sensors
- Detent switch
- Forkbolt primary switch
- Forkbolt secondary switch
- Sector gear close switch
- Sector gear open switch
During power opening and/or power closing operation, the LTM (Liftgate/Trunk Module) provides output to the power liftgate motor, cinch motor, and chime.
For detailed description of normal operation, refer to Principles of Operation.
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Power liftgate latch
- Power liftgate motor
- LTM (Liftgate/Trunk Module)
PINPOINT TEST A : THE POWER LIFTGATE IS INOPERATIVE - DOES NOT OPEN OR CLOSE
NOTICE: Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
A1 CHECK THE OPERATION OF THE POWER LIFTGATE SWITCHES
- Vehicle in park.
- NOTE: Make sure the power liftgate is enabled (on) in the vehicle message center.
Close the liftgate to the full closed position (manually if necessary).
- Activate the power liftgate from the power liftgate control switch (instrument panel).
- Activate the power liftgate from an Remote Keyless Entry (RKE) transmitter.
- Activate the power liftgate from the exterior liftgate switch.
Does the power liftgate power open from any switch?
Yes
GO to Pinpoint Test B. Pinpoint Test B: Power Liftgate Is Inoperative From an Individual Switch
No
GO to A2.
A2 RETRIEVE THE DTCs FROM THE LTM (Liftgate/Trunk Module)
- Use the recorded Liftgate/Trunk Module (LTM) DTCs from the self-test.
Are any LTM (Liftgate/Trunk Module) DTCs recorded?
Yes
For DTC B2552, GO to A3.
For DTC B2908, GO to A5.
For DTC B2418, B2419, or B2420, GO to A10.
For DTC B1179, B117A, B117B, B2936, B2819, or B2937, GO to A19.
For all other LTM (Liftgate/Trunk Module) DTCs, REFER to Liftgate/Trunk Module (LTM) DTC chart Trunk / Liftgate.
No
GO to A3.
A3 CHECK FOR VOLTAGE TO THE LTM (Liftgate/Trunk Module)
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174A.
- Measure the voltage between the LTM (Liftgate/Trunk Module) C4174A-9, circuit SBP09 (RD), harness side and ground; and between the LTM (Liftgate/Trunk Module) C4174A-4, circuit SBB07 (WH/RD), harness side and ground.
Are the voltages greater than 10 volts?
Yes
GO to A4.
No
VERIFY Body Control Module (BCM) fuse 9 (10A) or the Battery Junction Box (BJB) fuse 7 (30A) is OK. If OK, REPAIR the circuit in question for an open. TEST the system for normal operation.
If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short [1][2]Diagrams By Number. TEST the system for normal operation.
A4 CHECK THE LTM (Liftgate/Trunk Module) GROUND FOR AN OPEN
- Measure the resistance between LTM (Liftgate/Trunk Module) C4174A-1, circuit GD149 (BK/GY), harness side and ground.
Is the resistance less than 5 ohms?
Yes
RECONNECT the LTM (Liftgate/Trunk Module) C4174A and GO to A5.
No
REPAIR circuit GD149 (BK/GY) for an open. TEST the system for normal operation.
A5 CHECK THE DETENT AND FORKBOLT SWITCH PIDs
- Enter the following diagnostic mode on the scan tool: LTM (Liftgate/Trunk Module) DataLogger.
- Operate the liftgate manually while monitoring the following LTM (Liftgate/Trunk Module) PIDs:
- Detent Switch Status (DETENTSW)
- Forkbolt Switch Status (FORKBLT_S)
- Forkbolt Secondary Switch (FKSWSEC)
- NOTE: The liftgate is in the primary position when the liftgate is in the full closed position. The liftgate is in the unlatch position when the liftgate is open and completely out of the striker.
Begin with the liftgate in the open position, then slowly close the liftgate into each of the latch positions specified by the table below.
Liftgate Latch Position DETENTSW FORKBLT_S FKSWSEC Fully Unlatched Inactive (a)Active Active Primary Active Inactive Inactive
(a) If detent switch is active in the fully unlatched position, manually attempt to rotate the forkbolt towards the latched position.
Do the switch states agree with the table?
Yes
GO to A10.
No
GO to A6.
A6 CHECK THE OPERATION OF THE DETENT AND FORKBOLT SWITCHES
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174B.
- Measure the resistance between LTM (Liftgate/Trunk Module) C4174B, harness side and ground at each of the connector pins and each latch position specified by the table below.
Liftgate Latch Position LTM (Liftgate/Trunk Module) Connector-Pin Circuit Resistance Fully Unlatched C4174B-3 CPR66 (GY/YE) Greater than 10,000 ohms (a)Fully Unlatched C4174B-5 CPR64 (VT/OG) Less than 5 ohms Fully Unlatched C4174B-4 CPR65 (BU/GN) Less than 5 ohms Primary C4174B-3 CPR66 (GY/YE) Less than 5 ohms Primary C4174B-5 CPR64 (VT/OG) Greater than 10,000 ohms Primary C4174B-4 CPR65 (BU/GN) Greater than 10,000 ohms
(a) If resistance measured is less than 5 ohms, manually rotate the forkbolt to the latched position and retest.
Do the resistance values agree with the table?
Yes
GO to A10.
No
GO to A7.
A7 CHECK THE DETENT AND FORKBOLT SWITCH GROUND CIRCUIT
- Disconnect: Power Liftgate Latch C4339.
- Measure the resistance between power liftgate latch C4339-8, circuit GD149 (BK/GY), harness side and ground.
Is the resistance less than 5 ohms?
Yes
GO to A8.
No
REPAIR the circuit for an open. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A8 CHECK THE DETENT AND FORKBOLT SWITCH CIRCUITS FOR AN OPEN
- Measure the resistance between power liftgate latch C4339, harness side and LTM (Liftgate/Trunk Module) C4174B, harness side using the following table:
Power Liftgate Latch Connector-Pin Circuit LTM (Liftgate/Trunk Module) Connector-Pin C4339-2 CPR64 (VT/OG) C4174B-5 C4339-3 CPR65 (BU/GN) C4174B-4 C4339-5 CPR66 (GY/YE) C4174B-3
Is the resistance less than 5 ohms on all circuits?
Yes
GO to A9.
No
REPAIR the circuit in question for an open. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A9 CHECK THE DETENT AND FORKBOLT SWITCH CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between the LTM (Liftgate/Trunk Module) C4174B-5, circuit CPR64 (VT/OG), harness side and ground; then between the LTM (Liftgate/Trunk Module) C4174B-4, circuit CPR65 (BU/GN), harness side and ground; then between the LTM (Liftgate/Trunk Module) C4174B-3, circuit CPR66 (GY/YE), harness side and ground.
Is the resistance greater than 10,000 ohms on all circuits?
Yes
INSTALL a new power liftgate latch. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
No
REPAIR the circuit in question for a short to ground. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A10 CHECK THE LIFTGATE POSITION SENSOR (OPT_SEN_1) AND (OPT_SEN_2) PIDs
- Ignition ON.
- Open the liftgate to the full OPEN position.
- Enter the following diagnostic mode on the scan tool: LTM (Liftgate/Trunk Module) DataLogger.
- Monitor the LTM (Liftgate/Trunk Module) PIDs OPT_SEN_1 and OPT_SEN_2 while slowly closing the liftgate.
Do both of the PID values alternate from ACTIVE to INACTIVE while the liftgate is moving?
Yes
GO to A19.
No
GO to A11.
A11 CHECK FOR VOLTAGE TO THE POSITION SENSOR
- Ignition OFF.
- Disconnect: Power Liftgate Motor C4223.
- Ignition ON.
- Measure the voltage between the power liftgate motor C4223-2, circuit CPR55 (GN/BU), harness side and the power liftgate motor C4223-3, circuit RPR55 (WH/BU), harness side.
Is the voltage approximately 5 volts?
Yes
GO to A15.
No
GO to A12.
A12 CHECK THE POSITION SENSOR VOLTAGE CIRCUIT
- Measure the voltage between power liftgate motor C4223-2, circuit CPR55 (GN/BU), harness side and ground.
Is the voltage approximately 5 volts?
Yes
GO to A14.
No
GO to A13.
A13 CHECK THE POSITION SENSOR VOLTAGE CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174B.
- Measure the resistance between LTM (Liftgate/Trunk Module) C4174B-6, circuit CPR55 (GN/BU), harness side and power liftgate motor C4223-2, circuit CPR55 (GN/BU), harness side; and between LTM (Liftgate/Trunk Module) C4174B-6, circuit CPR55 (GN/BU), harness side and ground.
Is the resistance less than 5 ohms between LTM (Liftgate/Trunk Module) and power liftgate motor; and greater than 10,000 ohms between
LTM (Liftgate/Trunk Module) and ground?
Yes
GO to A24.
No
REPAIR the circuit for an open or short to ground. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A14 CHECK THE POSITION SENSOR RETURN CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174B.
- Measure the resistance between the LTM (Liftgate/Trunk Module) C4174B-7, circuit RPR55 (WH/BU), harness side and the power liftgate motor C4223-3, circuit RPR55 (WH/BU), harness side.
Is the resistance less than 5 ohms?
Yes
GO to A24.
No
REPAIR the circuit for an open. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A15 CHECK THE POSITION SENSOR CIRCUITS FOR REFERENCE VOLTAGE
- Ignition ON.
- Measure the voltage between the power liftgate motor C4223-5, circuit VPR53 (BU/WH), harness side and ground; and between the power liftgate motor C4223-6, circuit VPR54 (BU/BN), harness side and ground.
Are the voltages approximately 5 volts?
Yes
INSTALL a new power liftgate motor. REFER to Power Liftgate Motor Service and Repair. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
No
GO to A16.
A16 CHECK THE POSITION SENSOR CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174B.
- Measure the resistance between the power liftgate motor C4223, harness side and the LTM (Liftgate/Trunk Module) C4174B, harness side using the following chart:
Power Liftgate Motor Connector-Pin Circuit LTM (Liftgate/Trunk Module) Connector-Pin C4223-5 VPR53 (BU/WH) C4174B-20 C4223-6 VPR54 (BU/BN) C4174B-21
Are the resistances less than 5 ohms?
Yes
GO to A17.
No
REPAIR the circuit in question for an open. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A17 CHECK THE POSITION SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between the power liftgate motor C4223-5, circuit VPR53 (BU/WH), harness side and ground; and between the power liftgate motor C4223-6, circuit VPR54 (BU/BN), harness side and ground.
Is any voltage present?
Yes
REPAIR the circuit in question for a short to voltage. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
No
GO to A18.
A18 CHECK THE POSITION SENSOR CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between the power liftgate motor C4223-5, circuit VPR53 (BU/WH), harness side and ground; and between the power liftgate motor C4223-6, circuit VPR54 (BU/BN), harness side and ground.
Are the resistances greater than 10,000 ohms?
Yes
GO to A24.
No
REPAIR the circuit in question for an open. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A19 CHECK THE MOTOR AND LATCH CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between the LTM (Liftgate/Trunk Module) C4174A, harness side and ground as follows:
LTM (Liftgate/Trunk Module) Connector-Pin Circuit C4174A-2 CPR61 (BN) C4174A-3 CPR62 (WH/BU) C4174A-5 CPR57 (GN/WH) C4174A-6 CPR58 (GN/OG)
Is any voltage present?
Yes
REPAIR the circuit in question for a short to voltage. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
No
GO to A20.
A20 CHECK THE MOTOR AND LATCH CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174A.
- Disconnect: Power Liftgate Motor C4223.
- Disconnect: Power Liftgate Latch C4339.
- Measure the resistance between the LTM (Liftgate/Trunk Module) C4174A, harness side and ground as follows:
LTM (Liftgate/Trunk Module) Connector-Pin Circuit C4174A-2 CPR61 (BN) C4174A-3 CPR62 (WH/BU) C4174A-5 CPR57 (GN/WH) C4174A-6 CPR58 (GN/OG)
Are the resistances greater than 10,000 ohms?
Yes
GO to A21.
No
REPAIR the circuit in question for a short to ground. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A21 CHECK THE MOTOR AND LATCH CIRCUITS FOR AN OPEN
- Ignition OFF.
- Measure the resistance between the LTM (Liftgate/Trunk Module) C4174A, harness side and the power liftgate motor C4223, harness side, or the power liftgate latch C4339, harness side using the following chart:
LTM (Liftgate/Trunk Module) Connector-Pin Circuit Power Liftgate Motor Connector-Pin C4174A-5 CPR57 (GN/WH) C4223-1 C4174A-6 CPR58 (GN/OG) C4223-4 C4174A-2 CPR61 (BN) C4339-1 C4174A-3 CPR62 (WH/BU) C4339-4
Are the resistances less than 5 ohms?
Yes
GO to A22.
No
REPAIR the circuit in question for an open. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A22 CHECK THE UNLATCH OPERATION
- Connect: Power Liftgate Latch C4339.
- Close and latch the liftgate.
- NOTICE: Do not apply power and ground to the unlatch actuator circuits for more than a few seconds or damage to the motor may occur.
Momentarily connect a fused jumper wire between LTM (Liftgate/Trunk Module) C4174A-3, circuit CPR62 (WH/BU), harness side and the LTM (Liftgate/Trunk Module) C4174A-4, circuit SBB07 (WH/RD), harness side; and connect a fused jumper wire between the LTM (Liftgate/Trunk Module) C4174A-2, circuit CPR61 (BN), harness side and the LTM (Liftgate/Trunk Module) C4174A-1, circuit GD149 (BK/GY), harness side.
Does the unlatch/cinching motor activate?
Yes
LEAVE the liftgate unlatched, GO to A23.
No
INSTALL a new power liftgate latch. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A23 CHECK THE POWER LIFTGATE MOTOR OPERATION
- Connect: Power Liftgate Motor C4223.
- Liftgate in the fully closed and unlatched position.
- NOTICE: Do not apply power and ground to the motor actuator circuits for more than a few seconds or damage to the motor may occur.
Momentarily connect a fused jumper wire between LTM (Liftgate/Trunk Module) C4174A-5, circuit CPR57 (GN/WH), harness side and the LTM (Liftgate/Trunk Module) C4174A-4, circuit SBB07 (WH/RD), harness side; and connect a fused jumper wire between the LTM (Liftgate/Trunk Module) C4174A-6, circuit CPR58 (GN/OG), harness side and the LTM (Liftgate/Trunk Module) C4174A-1, circuit GD149 (BK/GY), harness side.
Does the power liftgate motor operate?
Yes
GO to A24.
No
INSTALL a new power liftgate motor. REFER to Power Liftgate Motor Service and Repair. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
A24 CHECK FOR CORRECT LTM (Liftgate/Trunk Module) OPERATION
- Disconnect all the LTM (Liftgate/Trunk Module) connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the LTM (Liftgate/Trunk Module) connectors and make sure they are seated correctly.
- Make sure the liftgate is fully CLOSED.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new LTM (Liftgate/Trunk Module). REFER to Liftgate/Trunk Module (LTM) Service and Repair. TEST the system for normal operation.
No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.