A Symptom Diagnosis

IMPORTANT: The following steps must be completed before using the symptom tables.
1. Perform Diagnostic System Check - Instrument Cluster, Diagnostic System Check - Driver Information Systems or Diagnostic System Check - Audible Warnings 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 link. Diagnostic System Check - Instrument Panel Cluster Diagnostic System Check - Driver Information Systems Diagnostic System Check - Audible Warnings
2. Review the system operation in order to familiarize yourself with the system functions. Refer to the following:
- Instrument Panel Cluster (IPC) 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 Diagnostic Aids.
- 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 Diagnostic Aids for Circuit Testing and Wiring Repair procedures.

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

Gages and Odometer
- Instrument Cluster Inoperative
- Instrument Cluster Inoperative
- Engine Oil Pressure Gage Inaccurate or Inoperative
- Fuel Gage Inaccurate or Inoperative (Dual Tanks)Fuel Gage Inaccurate or Inoperative (Single Tank)
- Hourmeter Inaccurate or Inoperative
- Instrument Panel Cluster (IPC) Gages Inoperative
- Odometer Trip/Reset Switch Inoperative
- Transmission Fluid Temperature 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 Restraint Systems
- Brake Warning Indicator Always On in Hydraulic Brakes
- Brake Warning Indicator Inoperative in Hydraulic Brakes
- Charge Indicator Always On in Starting and Charging
- Charge Indicator Inoperative in Starting and Charging
- Cruise Control Indicator Always On in Cruise Control
- Cruise Control Indicator Inoperative in Cruise Control
- High Beam Indicator Inoperative in Lighting Systems
- Malfunction Indicator Lamp (MIL) Inoperative in Computers and Control Systems - 4.8L, 5.3L, and 6.0L
- Malfunction Indicator Lamp (MIL) Always On in Computers and Control Systems - 4.8L, 5.3L, and 6.0L
- Security Indicator Always On or Flashing in Theft Deterrent
- Security Indicator Inoperative in Theft Deterrent
- Service Indicator Always On in Transfer Case - BW 4482 - NR4
- Service Indicator Inoperative in Transfer Case - BW 4482 - NR4
- Service Indicator Always On in Transfer Case - NVG 246 - NP8
- Service Indicator Inoperative in Transfer Case - NVG 246 - NP8
- Tow/Haul Switch/Indicator Always On or Inoperative in Automatic Transmission - 4L60E
- Turn Signal Lamps and/or Indicators Always On or Flashing in Lighting Systems
- Turn Signal Lamps and/or Indicators Inoperative in Lighting Systems

Message Center
- Change Engine Oil Indicator Always On
- Engine Overheated Indicator Always On in Cooling System
- Engine Coolant Temperature Indicator Always On in Cooling System
- Low Engine Coolant Indicator Always On in Cooling System
- Low Engine Oil Level Indicator Always On
- Low Washer Fluid Indicator Malfunction in Wipers/Washer Systems

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(es) Inoperative

Audible Warnings
- Chime Always On
- Chime Inoperative