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B1953

B1953-POWER LIFTGATE LATCH CINCH OVERCURRENT

WHEN MONITORED
Whenever the power liftgate is performing a cinching operation.

SET CONDITION
The latch motor stall current of 12.0 amps has been detected for over 500 ms, with no pawl or ratchet failure.

POSSIBLE CAUSES
- Binding liftgate
- Latch not in home position
- (Q84) Liftgate latch cinch driver wire open
- (Q85) Liftgate latch release driver open
- (Q84) Liftgate latch cinch driver wire short to ground
- (Q84) Liftgate latch cinch driver wire short to the (Q901) logic ground
- (Q85) Liftgate latch release driver wire short to ground
- (Q85) Liftgate latch release driver wire short to the (Q901) logic ground
- (Q84) Liftgate latch cinch driver wire short to voltage
- Latch assembly

Diagnostic Test

1. DTC PRESENT

Ensure the liftgate is closed and with the scan tool, run the "Latch Home Position Test" before proceeding to ensure the latch is positioned correctly.
With the scan tool, record and erase DTC's.
Turn the ignition off, wait 10 seconds, then turn the ignition on.
Operate the power liftgate several times if possible.
With the scan tool, read ACTIVE DTCs.

Q: Does the scan tool display B1953-POWER LIFTGATE LATCH CINCH OVERCURRENT?

YES: Go To 2
NO: Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for an intermittent condition. Operate the liftgate several times and check for any binding or other obstructions. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

2. BINDING LIFTGATE

Examine the liftgate for proper alignment, worn or binding hinges, weak liftgate prop assembly, loose/hard weatherstrip, and track assembly for wear or anything that would cause an obstruction to proper operation.
If necessary manually operate the power liftgate on a known good vehicle and notice the effort needed to open and close for comparison.
Especially notice the effort needed to unlatch and close the liftgate.

Q: Were there any mechanical problems found?

YES: Refer to Service information for the related symptom(s). Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 3

3. (Q84) LIFTGATE LATCH CINCH DRIVER CIRCUIT OPEN




Turn the ignition off.
Disconnect the Power Liftgate Module C2 connector.
Disconnect the Power Liftgate Latch connector.
Measure the resistance of the (Q84) Liftgate Latch Cinch Driver circuit between the Power Liftgate Module C2 connector and the Power Lift-gate Latch connector.
Wiggle the harness and check for an intermittent open condition.

Q: Is the resistance below 5.0 ohms?

YES: Go To 4
NO: Repair the (Q84) Liftgate Latch Cinch Driver wire for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

4. (Q85) LIFTGATE LATCH RELEASE DRIVER CIRCUIT OPEN




Measure the resistance of the (Q85) Liftgate Latch Release Driver circuit between the Power Liftgate Module C2 connector and the Power Liftgate Latch connector.
Wiggle the harness and check for an intermittent open condition.

Q: Is the resistance below 5.0 ohms?

YES: Go To 5
NO: Repair the (Q85) Liftgate Latch Release Driver wire for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

5. (Q84) LIFTGATE LATCH CINCH DRIVER CIRCUIT SHORT TO GROUND




Measure the resistance between ground and the (Q84) Liftgate Latch Cinch Driver circuit.
Wiggle the harness and check for an intermittent short condition.

Q: Is the resistance below 1000.0 ohms?

NO: Go To 6
YES: Repair the (Q84) Liftgate Latch Cinch Driver wire for a short to ground. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

6. (Q84) LIFTGATE LATCH CINCH DRIVER CIRCUIT SHORT TO (Q901) LOGIC GROUND




Measure the resistance between the (Q901) Logic Ground circuit and the (Q84) Liftgate Latch Cinch Driver circuit.
Wiggle the harness and check for an intermittent short condition.

Q: Is the resistance below 1000.0 ohms?

NO: Go To 7
YES: Repair the (Q84) Liftgate Latch Cinch Driver wire for a short to the (Q901) Logic Ground circuit. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

7. (Q84) LIFTGATE LATCH RELEASE DRIVER WIRE SHORT TO GROUND




Measure the resistance between ground and the (Q84) Liftgate Latch Release Driver circuit.
Wiggle the harness and check for an intermittent short condition.

Q: Is the resistance below 1000.0 ohms?

NO: Go To 8
YES: Repair the Liftgate Latch Release Driver wire for a short to ground. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

8. (Q85) LIFTGATE LATCH RELEASE DRIVER WIRE SHORT TO (Q901) LOGIC GROUND




Measure the resistance between the (Q901) Logic Ground circuit and the (Q85) Liftgate Latch Release Driver circuit.
Wiggle the harness and check for an intermittent short condition.

Q: Is the resistance below 1000.0 ohms?

NO: Go To 9
YES: Repair the (Q85) Liftgate Latch Release Driver wire for a short to the Ground circuit. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

9. (Q84) LIFTGATE LATCH CINCH DRIVER WIRE SHORT TO VOLTAGE




Reconnect the Power Liftgate Module C2 connector Turn the ignition on.
Measure the voltage between the (Q84) Liftgate Latch Cinch Driver circuit and ground.

Q: Is there any voltage present?

NO: Replace the Latch Assembly. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
YES: Repair the (Q84) Liftgate Latch Cinch Driver wire for a short to voltage. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test