Power Liftgate

U0019-CAN B BUS





For a complete wiring diagram refer to Diagrams/Electrical.

- When Monitored:

When the key is on for more than 5 seconds

- Set Condition:

If the CAN B Bus (+) or CAN B Bus (-) circuit is open, shorted to voltage, shorted together, or shorted to ground.





Diagnostic Test

1. VERIFY DTC U0019-CAN B BUS IS ACTIVE

Turn the ignition on.

With the scan tool, read PLGM DTCs.

Does the scan tool display active: U0019-CAN B BUS?

Yes

- Go To 2

No

- If the DTC is stored, check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

2. CHECK FOR ACTIVE CAN B BUS RELATED DTCS IN THE BODY CONTROL MODULE (BCM)

With the scan tool, read Body Control Module (BCM) DTCs

Does the scan tool display any active CAN B BUS related DTCs?

Yes

- Diagnose and repair the DTC(s).

No

- Go To 3

3. CHECK (D55) CAN B BUS (+) CIRCUIT FOR AN OPEN





Turn the ignition off.

Disconnect the negative battery cable.

Disconnect the Power Liftgate Module C2 connector.

Disconnect the Body Control Module (BCM) C3 harness connector.

Measure the resistance of the (D55) CAN B Bus (+) circuit between the Body Control Module C3 harness connector and the Power Liftgate Module C2 connector.

Is the resistance below 2.0 ohms?

Yes

- Go To 4

No

- Repair the (D55) CAN B Bus (+) circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

4. CHECK (D54) CAN B BUS (-) CIRCUIT FOR AN OPEN





Measure the resistance of the (D54) CAN B Bus (-) circuit between the Body Control Module C3 connector and the Power Liftgate Module C2 connector.

Is the resistance below 2.0 ohms?

Yes

- Go To 5

No

- Repair the (D54) CAN B Bus (-) circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

5. CHECK THE (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO VOLTAGE

Turn the ignition on.

Measure the voltage of the (D54) CAN B Bus (-) circuit.

Is there any voltage present?

Yes

- Repair the (D54) CAN B Bus (-) circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 6

6. CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO VOLTAGE

Turn the ignition on.

Measure the voltage of the (D55) CAN B Bus (+) circuit.

Is there any voltage present?

Yes

- Repair the (D55) CAN B Bus (+) circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 7

7. CHECK THE (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO GROUND

Turn the ignition off.

Measure the resistance between ground and the (D54) CAN B Bus (-) circuit.

Is the resistance below 100 ohms?

Yes

- Repair the (D54) CAN B Bus (-) circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 8

8. CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO VOLTAGE

Turn the ignition off.

Measure the resistance between ground and the (D55) CAN B Bus (+) circuit.

Is the resistance below 100 ohms?

Yes

- Repair the (D55) CAN B Bus (+) circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

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