Important: The following steps must be completed before using the symptom tables.
| • | Perform the Diagnostic System Check - Vehicle in Vehicle DTC Information before using the Symptom Tables in order to verify that all of the following are true: | 
| - | There are no DTCs set. | 
| - | The control modules can communicate via the serial data link. | 
| • | Review the system description and operation in order to familiarize yourself with the system. | 
Refer to Luggage Compartment Description and Operation .
| • | Inspect for aftermarket devices which could affect the operation of the body rear end. Refer to Checking Aftermarket Accessories in Wiring Systems. | 
| • | Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom. | 
Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom: