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A Symptoms - Computer/Integrating Systems



SYMPTOMS

IMPORTANT: The following steps must be completed before using the symptom tables.

1. 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 links. Diagnostic System Check - Vehicle
2. Review the system operation in order to familiarize yourself with the system functions. Refer to:
- Data Link Communications Description and Operation
- Body Control System Description Retained Accessory Power (RAP) Description and Operation

Visual/Physical Inspection
- Inspect for aftermarket devices which could affect the operation of the systems.
- Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

INTERMITTENT
Faulty electrical connections or wiring may be the cause of intermittent conditions.

Symptom List
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

- Scan Tool Does Not Power Up Symptom Related Diagnostic Procedures

- Scan Tool Does Not Communicate with Class 2 Device Symptom Related Diagnostic Procedures

- Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate With High Speed GMLAN Device

- Scan Tool Does Not Communicate with Low Speed GMLAN Device Scan Tool Does Not Communicate With Low Speed GMLAN Device

- Retained Accessory Power (RAP) On After Timeout Retained Accessory Power (RAP) On After Timeout

- Retained Accessory Power (RAP) Inoperative Retained Accessory Power (RAP) Inoperative