GM Service Manual Online
For 1990-2009 cars only

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

  1. Perform Diagnostic System Check - Vehicle , before using the Symptom Tables in order to verify that all of the following are true:
  2. • There are no DTCs set.
    • The control modules can communicate via the serial data link.
  3. Review the system operation in order to familiarize yourself with the system functions. Refer to Keyless Entry System Description and Operation and Garage Door Opener Description and Operation .

Visual/Physical Inspection

    • Turn the ignition key to the ON position and press any garage door opener (GDO) button. The LED should light when the unit has power and is functional.
    • Inspect for aftermarket devices which could affect the operation of the Keyless Entry System or the Garage Door Opener. Refer to Checking Aftermarket Accessories .
    • 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 to Testing for Intermittent Conditions and Poor Connections .

Symptom List

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

    •  Garage Door Opener Inoperative
    •  Keyless Entry System Inoperative
    •  Panic Mode Inoperative
    •  Remote Vehicle Start Inoperative