GM Service Manual Online
For 1990-2009 cars only

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

  1. Perform the Rear Wheel Steering Diagnostic System Check before using the symptom tables in order to verify that the following conditions are true:
  2.    • DTCs are not set.
       • The control modules can communicate via the serial data link.
  3. Review the system description and operation in order to familiarize yourself with the system functions. Refer to Rear Wheel Steering Description and Operation .

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the Rear Wheel Steering System. 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.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

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

    •  Service Four-Wheel Steer Indicator Always On
    •  Service Four-Wheel Steer Indicator Inoperative