B1955

B1955-POWER LIFTGATE LATCH RELEASE OVERCURRENT





For a complete wiring diagram Consult Diagrams/Electrical

NOTE: If there are any other Power Liftgate DTC's present, correct them before proceeding with this test.

- When Monitored:
Whenever the power liftgate is performing a releasing operation.

- Set Condition:
The Liftgate Cinch/Release Motor stall current of over 6.2 amps has been detected for over 200ms. with no pawl or ratchet failure





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.
Does the scan tool display B1955-POWER LIFTGATE LATCH RELEASE 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 hinge 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.
Were there any mechanical problems found?

Yes

- Repair accordingly.
- PERFORM BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 3

3. (Q84) LIFTGATE LATCH CINCH DRIVER CIRCUIT SHORT TO VOLTAGE




Turn the ignition off.
Disconnect the Power Liftgate Module C2 connector.
Turn the ignition on.
Measure the voltage between the (Q84) Liftgate Latch Cinch Driver circuit and ground.
Is there any voltage present?

Yes

- Go To 4

No

- Go To 5

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




Disconnect the Liftgate Cinch/Release Motor connector.
Measure the voltage between the (Q84) Liftgate Latch Cinch Driver circuit and ground
Is there any voltage present?

Yes

- Repair the (Q84) Liftgate Latch Cinch Driver wire for a short to voltage.
- PERFORM BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Repair the (Q85) Liftgate Latch Release Driver wire for a short to voltage.
- PERFORM BODY VERIFICATION TEST - VER 1. Body Verification Test

5. (Q901) LOGIC GROUND CIRCUIT OPEN




Measure the resistance of the (Q901) Logic Ground wire between the Power Liftgate Module C2 connector and the Liftgate Cinch/Release Motor connector.
Is the resistance below 2.0 ohms?

Yes

- Go To 6

No

- Repair the (Q901) Logic Ground wire for an open.
- PERFORM BODY VERIFICATION TEST - VER 1. Body Verification Test

6. (G78) LIFTGATE AJAR SWITCH SENSE WIRE OPEN




Measure the resistance of the (G78) Liftgate Ajar Switch Sense wire between the Power Liftgate Module C2 connector and the Liftgate Cinch/Release Motor connector.
Is the resistance below 5.0 ohms?

Yes

- Replace the Liftgate Cinch/Release Motor Assembly.
- PERFORM BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Repair the (G78) Liftgate Ajar Switch Sense wire for an open.
- PERFORM BODY VERIFICATION TEST - VER 1. Body Verification Test