GM Service Manual Online
For 1990-2009 cars only

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

  1. Before using the symptom diagnostic tables, perform the Diagnostic System Check - Vehicle in order to verify the following conditions:
  2. • There are not any DTCs set.
    • The control modules can communicate via the serial data link.
  3. Review the system operation in order to understand the system functions. Refer to the following description and operations:
  4. •  Instrument Cluster Description and Operation
    •  Indicator/Warning Message Description and Operation
    •  Audible Warnings Description and Operation

Visual/Physical Inspection

    • Inspect for aftermarket devices which can affect the operation of the instrument panel cluster or the audible warnings system. Refer to Checking Aftermarket Accessories .
    • Inspect the accessible system components or the visible system components for obvious damage or for obvious conditions which can cause the symptom.
    • Inspect for the proper fluid levels.

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:

Gages and Odometer

    •  Engine Oil Pressure Gage Inaccurate or Inoperative
    •  Fuel Gage Inaccurate or Inoperative
    •  Instrument Cluster Inoperative
    •  Instrument Cluster Gages Inoperative

Indicators

    •  ABS Indicator Always On
    •  ABS Indicator Inoperative
    •  Air Bag Indicator Circuit Malfunction
    •  Brake Warning Indicator Always On
    •  Brake Warning Indicator Inoperative
    •  Change Engine Oil Indicator Always On
    •  Change Engine Oil Indicator Inoperative
    •  Charge Indicator Always On
    •  Charge Indicator Inoperative
    •  Rear Fog Lamp Indicator Inoperative
    •  High Beam Indicator Always On
    •  High Beam Indicator Inoperative
    •  Low Engine Oil Level Indicator Always On
    •  Low Fuel Indicator Inoperative
    •  Malfunction Indicator Lamp (MIL) Inoperative for the 4.3L engine
    •  Malfunction Indicator Lamp (MIL) Always On for the 4.3L engine
    •  Malfunction Indicator Lamp (MIL) Always On for the 4.8L, 5.3L, and 6.0L engine
    •  Malfunction Indicator Lamp (MIL) Inoperative for the 4.8L, 5.3L, and 6.0L engine
    •  Malfunction Indicator Lamp (MIL) Diagnosis for the 6.6L (LBZ and LLY) engine
    •  Malfunction Indicator Lamp (MIL) Diagnosis for the 6.6L (LMM) engine
    •  Mirror Compass Display Inoperative or Inaccurate
    •  Mirrors - Temperature Display Inaccurate
    •  Mirrors - Temperature Displays SC or OC
    •  Passenger Presence System Indicator Circuit Malfunction
    •  Seat Belt Indicator Circuit Malfunction - Driver
    •  Seat Belt Indicator Circuit Malfunction - Passenger
    •  Security Indicator Always On or Flashing
    •  Security Indicator Inoperative
    •  Stability System Caution Indicator Always On
    •  Stability System Caution Indicator Inoperative
    •  Stability System Not Ready Indicator Always On
    •  Stability System Not Ready Indicator Inoperative
    •  Tow/Haul Switch/Indicator Always On or Inoperative for the 4L60-E transmission
    •  Turn Signal Lamps and/or Indicators Always On or Flashing
    •  Turn Signal Lamps and/or Indicators Inoperative
    •  Water-in-Fuel Lamp Always On
    •  Water-in-Fuel Lamp Inoperative

Audible Warnings

    •  Chime Always On
    •  Chime Inoperative