Symptoms - Computer/Integrating Systems. GMC Truck GMC C Sierra

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2005 🢒 GMC C Sierra - 2WD 🢒 General Information 🢒 Vibration Diagnosis and Correction 🢒 Symptoms - Computer/Integrating Systems

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 links.

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 and Operation

•	Retained Accessory Power (RAP) Description and Operation

•	Inspect for aftermarket devices which could affect the operation of the systems. 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:

•	Scan Tool Does Not Power Up

•	Scan Tool Does Not Communicate with Class 2 Device

•	Scan Tool Does Not Communicate with High Speed GMLAN Device

•	Power Mode Mismatch

•	Retained Accessory Power (RAP) On After Timeout

•	Retained Accessory Power (RAP) Inoperative