Power Liftgate System Diagnosis

The power liftgate system contains many components and modules. In order to obtain conclusive testing the Programmable Communications Interface (PCI) data bus network and all of the electronic modules that provide inputs to, or receive outputs from the power liftgate system must be checked.

The power liftgate system can be diagnosed with an appropriate scan tool, such as the DRB III (R) or equivalent. The DRB III (R) can be used to observe various switch statuses throughout the power liftgate system to help diagnose an inoperative switch or component. The DRB III (R) can also be used to actuate various components throughout the power liftgate system to help diagnose an inoperative component.

Before any testing of the power liftgate system is attempted, the battery should be fully charged, all built-in power liftgate system inhibitors read and understood, and all wire harness and ground connections inspected around the affected areas on the vehicle.

Liftgate System Diagnosis Part 1:

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The following are quick reference diagnostic tables to help when diagnosing and testing the power lift-gate system.