Diagnostic Test

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 DTCs.

Does the scan tool display B1968-POWER LIFTGATE OPEN DIRECTION - EXCESSIVE TIME? 

Yes 

1. Go to  2).

No 

1. 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 conditions.
2. Perform BODY VERIFICATION TEST .

Examine the liftgate for proper alignment, worn or binding hinges, weak liftgate prop assembly, or loose/hard weatherstrip or anything that would cause an obstruction to proper operation.

If necessary manually operate the liftgate of a known good vehicle and notice the effort needed.

Compare the effort needed on the disabled vehicle.

Were there any mechanical problems found? 

Yes 

1. Refer to Service information for the related symptom(s).
2. Perform BODY VERIFICATION TEST .

No 

1. Go to  3).

Disconnect all Power Liftgate Module harness connectors.

Disconnect the Power Liftgate Drive Unit harness connector.

Check all connectors and terminals for corrosion.

Do any connectors or terminals need repairing? 

Yes 

1. Clean and repair wiring as necessary.
2. Perform BODY VERIFICATION TEST .

No 

1. Replace the Power Liftgate Drive Unit in accordance with the service information.
2. Perform BODY VERIFICATION TEST .