GM Service Manual Online
For 1990-2009 cars only

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:
  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 the following:
  4. •  Instrument Cluster Description and Operation
    •  Indicator/Warning Message Description and Operation
    •  Driver Information Center (DIC) Description and Operation
    •  Audible Warnings Description and Operation

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the Instrument Cluster or Audible Warning 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.
    • Inspect for proper fluid level.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to 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:

Gages and Odometer

    •  Instrument Cluster Inoperative
    •  Engine Oil Pressure Gage Inaccurate or Inoperative
    •  Fuel Gage Inaccurate or Inoperative
    •  Instrument Cluster Gages Inoperative
    •  Odometer Trip/Reset Switch Inoperative
    •  Speedometer and/or Odometer Inaccurate or Inoperative
    •  Tachometer Inaccurate or Inoperative
    •  Volt Gage Inaccurate or Inoperative
    •  Change Engine Oil Indicator Always On
    •  Low Engine Oil Level Indicator Always On

Indicators

    •  ABS Indicator Always On in Antilock Brake System
    •  ABS Indicator Inoperative in Antilock Brake System
    •  Air Bag Indicator Circuit Malfunction in SIR
    •  Brake Warning Indicator Always On in Hydraulic Brakes
    •  Brake Warning Indicator Inoperative in Hydraulic Brakes
    •  Change Engine Oil Indicator Always On
    •  Charge Indicator Always On in Engine Electrical
    •  Charge Indicator Inoperative in Engine Electrical
    •  Cruise Control Indicator Always On in Cruise Control
    •  Cruise Control Indicator Inoperative in Cruise Control
    •  Engine Coolant Temperature Indicator Always On in Engine Cooling
    •  Engine Overheated Indicator Always On in Engine Cooling
    •  High Beam Indicator Always On in Lighting Systems
    •  High Beam Indicator Inoperative in Lighting Systems
    •  Low Engine Coolant Indicator Always On in Engine Cooling
    •  Low Engine Oil Level Indicator Always On
    •  Low Washer Fluid Indicator Malfunction in Wipers/Washer Systems
    •  Malfunction Indicator Lamp (MIL) Inoperative in Engine Controls - 4.3L
    •  Malfunction Indicator Lamp (MIL) Always On in Engine Controls - 4.3L
    •  Malfunction Indicator Lamp (MIL) Inoperative in Engine Controls - 4.8L, 5.3L, and 6.0L
    •  Malfunction Indicator Lamp (MIL) Always On in Engine Controls - 4.8L, 5.3L, and 6.0L
    •  Malfunction Indicator Lamp (MIL) Inoperative in Engine Controls - 6.6L (LLY)
    •  Malfunction Indicator Lamp (MIL) Always On in Engine Controls - 6.6L (LLY)
    •  Security Indicator Always On or Flashing in Theft Deterrent
    •  Security Indicator Inoperative in Theft Deterrent
    •  Four-Wheel Drive Indicator Always On in Transfer Case - NVG 261 - NP2
    •  Four-Wheel Drive Indicator Inoperative in Transfer Case - NVG 261 - NP2
    •  Service Indicator Always On in Transfer Case - NVG 246 - NP8
    •  Service Indicator Inoperative in Transfer Case - NVG 246 - NP8
    •  Service Indicator Always On in Transfer Case - NVG 263 - NP1
    •  Service Indicator Inoperative in Transfer Case - NVG 263 - NP1
    •  Tow/Haul Switch/Indicator Always On or Inoperative in Automatic Transmission - 4L60-E
    •  Tow/Haul Switch/Indicator Always On or Inoperative in Automatic Transmission - 4L80-E
    •  Traction Off Indicator Always On in Antilock Brake System
    •  Traction Off Indicator Inoperative in Antilock Brake System
    •  Turn Signal Lamps and/or Indicators Always On or Flashing in Lighting Systems
    •  Turn Signal Lamps and/or Indicators Inoperative in Lighting Systems
    •  Water-in-Fuel Lamp Always On
    •  Water-in-Fuel Lamp Inoperative

Instrument Cluster Dimming

    •  Interior Backlighting Inoperative in Lighting Systems
    •  Interior Backlighting Does Not Dim in Lighting Systems

Driver Information Center (DIC)

Driver Information Center (DIC) Switch Inoperative

Audible Warnings

    •  Chime Always On
    •  Chime Inoperative

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

Review the system operation in order to familiarize yourself with the system function. Refer to Charging System Description and Operation in Engine Electrical.

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the Instrument Cluster Gages. Refer to Checking Aftermarket Accessories in Wiring Systems in 2005 C/K Truck Service Manual.
    • 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 in Wiring Systems in 2005 C/K Truck Service Manual.

Symptom List

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

Gages and Odometer

Voltmeter Gage Inaccurate or Inoperative

Instrument Cluster Dimming

Voltmeter Gage Lamp Inoperative in Lighting Systems