Pinpoint Test C: The Power Liftgate Does Not Operate Correctly - Stops In Secondary Latch Position (Does Not Pull Into Primary
Power Liftgate
Pinpoint Tests
Pinpoint Test C: The Power Liftgate Does Not Operate Correctly - Stops in Secondary Latch Position (Does Not Pull into Primary Latch Position)
Refer to Wiring Diagram Set 109, Power Liftgate/Retractable Running Board for schematic and connector information. Diagrams By Number
Normal Operation
When the power liftgate moves in the close direction, the Liftgate/Trunk Module (LTM) monitors the detent switch, secondary forkbolt switch and the primary forkbolt switch. When the combination of signals is received that indicates the liftgate has reached the secondary latch position, the LTM supplies 12 volts to the unlatch/cinching motor on circuit CPR61 (BN) and ground on circuit CPR62 (WH/BU). The unlatch/cinching motor rotates the latch mechanism which pulls the liftgate into primary latch position.
- DTC B2019 Liftgate Exceeded Time Allowed to Cinch Door - If the cinching sequence has been active for more than 5 seconds, the LTM will set this DTC.
- DTC B2908 Latch Switch Invalid - If switch signals are invalid at start of self-test or no signal transitions during releasing/cinching, the LTM will set this DTC.
This pinpoint test is intended to diagnose the following:
- Liftgate alignment
- Latch striker alignment
- Wiring, terminals or connectors
- Power liftgate latch
- LTM
PINPOINT TEST C: THE POWER LIFTGATE DOES NOT OPERATE CORRECTLY - STOPS IN SECONDARY LATCH POSITION (DOES NOT PULL INTO PRIMARY LATCH POSITION)
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C1 RETRIEVE THE DTCs FROM THE LTM
- Use the recorded LTM DTCs from the continuous and self-tests.
- Is power liftgate DTC B2019 present?
Yes
CHECK the liftgate alignment. REFER to Liftgate Alignment Adjustments. If OK, GO to C2.
No
GO to C2.
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C2 CHECK THE DETENT AND FORKBOLT SWITCH PID
- Enter the following diagnostic mode on the scan tool: DataLogger - LTM.
- Operate the liftgate manually while monitoring the following LTM 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. The liftgate can be placed in the unlatched position by lifting up on the liftgate handle.
- Begin with the liftgate in the open position, then slowly close the liftgate into each of the latch positions specified by the table below.
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 C7.
No
GO to C3.
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C3 CHECK THE OPERATION OF THE DETENT AND FORKBOLT SWITCHES
- Ignition OFF.
- Disconnect: LTM C4174A.
- Measure the resistance between LTM C4174A, harness side and ground at each of the connector pins and each latch position specified by the chart below.
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 chart?
Yes
GO to C7.
No
GO to C4.
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C4 CHECK THE DETENT AND FORKBOLT SWITCH GROUND CIRCUIT
- Disconnect: Power Liftgate Latch/Unlatch Assembly C4339.
- Measure the resistance between power liftgate latch C4339-8, circuit GD147 (BK/VT), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to C5.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM self-test.
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C5 CHECK THE DETENT AND FORKBOLT SWITCH CIRCUITS FOR AN OPEN
- Measure the resistance between power liftgate latch/unlatch assembly C4339, harness side and LTM C4174A, harness side using the following chart:
- Is the resistance less than 5 ohms on all circuits?
Yes
GO to C6.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM self-test.
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C6 CHECK THE DETENT AND FORKBOLT SWITCH CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between LTM C4174A-4, circuit CPR64 (VT/OG), harness side and ground; then between LTM C4174A-5, circuit CPR65 (BU/GN), harness side and ground; then between LTM C4174A-3, circuit CPR66 (GY/YE), harness side and ground.
- Is the resistance greater than 10,000 ohms on all circuits?
Yes
CHECK the power liftgate latch connectors for bent or corroded connections on the component side and harness side. REPAIR as necessary.
INSTALL a new power liftgate latch. CLEAR the DTCs. REPEAT the LTM self-test.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM self-test.
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C7 CHECK FOR CORRECT LTM OPERATION
- Disconnect all the LTM connectors.
- Check for:
- corrosion.
- pushed-out pins.
- Connect all the LTM 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. REFER to Liftgate/Trunk Module (LTM) Service and Repair. REPEAT the LTM self-test.
No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the LTM self-test.
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