Trouble Shooting Procedure (Back Door Control System)

NOTE: Back door control system is used to control the following systems on the back (rear liftgate) door: power window, back door lock, luggage compartment light and rear wiper/washer. Trouble shooting procedure is for any of these systems on the back (rear liftgate) door.

To ensure correct trouble shooting procedures are followed, trouble shooting should be done in the following sequence:

Record Customer Complaint

Ensure all customer complaints or observations are recorded.

Confirm Symptoms

Determine if original symptoms still exist.

Diagnose & Repair

Ensure back door Electronic Control Unit (ECU) is able to communicate with rest of multiplex control system. See MULTIPLEX CONTROL SYSTEMS - SEQUOIA article. Once proper communication with multiplex control system is established, trouble shoot appropriate system by symptom and perform appropriate test listed under SYSTEM TESTS. See SYMPTOM INDEX (BACK DOOR CONTROL SYSTEM) table under SYSTEM TESTS. When performing trouble shooting for back door control system, it may be necessary to perform pin voltage test for back door ECU to ensure proper voltage or input signal exists. See BACK DOOR ELECTRONIC CONTROL UNIT under PIN VOLTAGE TESTS.

Verification Procedure

Ensure all symptoms and/or complaints have been repaired.