B1891

B1891-POWER LIFTGATE CONTROL CIRCUIT 2 LOW





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
Whenever the Power Liftgate is power opening or closing.

- Set Condition:
When the Power Liftgate Module senses voltage below 1.5 volts on the (Q89) Liftgate Close Driver circuit prior to starting a liftgate power cycle, this code will set.





Diagnostic Test

1. DTC PRESENT
With the scan tool, record DTCs.
Erase DTC's
Turn the ignition off, wait 10 seconds, then turn the ignition on.
If possible, operate the liftgate several times.
With the scan tool, read DTCs.
Does the scan tool display B1891-POWER LIFTGATE CONTROL CIRCUIT 2 LOW?

Yes

- Go To 2

No

- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for an intermittent condition.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

2. (Q89) LIFTGATE CLOSE DRIVER CIRCUIT SHORT TO (Q88) LIFTGATE OPEN DRIVER CIRCUIT




Turn the ignition off.
Disconnect the Power Liftgate Module C1 harness connector.
Measure the resistance between the (Q89) Liftgate Close Driver circuit and the (Q88) Liftgate Open Driver circuit
Is the resistance below 3.0 ohms (should be approximately 4.3 ohms)?

No

- Go To 4

Yes

- Go To 3


3. POWER LIFTGATE DRIVE UNIT




Disconnect the Power Liftgate Drive Unit harness connector.
Measure the resistance between the (Q89) Liftgate Close Driver circuit and the (Q88) Liftgate Open Driver circuit.
Is the resistance below 1000.0 ohms?

Yes

- Repair the (Q89) Liftgate Close Driver circuit for a short to the (Q88) Liftgate Open Driver circuit.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Replace the Power Liftgate Driver Unit.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

4. (Q89) LIFTGATE CLOSE DRIVER CIRCUIT SHORT TO GROUND




Measure the resistance between ground and the (Q89) Liftgate Close Driver circuit.
Is the resistance below 1000.0 ohms?

Yes

- Repair the (Q89) Liftgate Close Driver circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Go To 5

5. (Q88) LIFTGATE OPEN DRIVER CIRCUIT SHORT TO GROUND




Reconnect the Power Liftgate Module C1 harness connector.
Measure the resistance between ground and the (Q88) Liftgate Open Driver circuit.
Is the resistance above 1000.0 ohms?

Yes

- Replace the Power Liftgate Module.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Repair the (Q88) Liftgate Open Driver circuit for a short to ground. If the (Q88) Liftgate Open Driver is OK, replace the Power Liftgate Drive Unit.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.