Identifying Instrument Cluster System Problems

NOTE: Perform SYMPTOM ID TEST 1A before proceeding with this test. For connector terminal identification and wiring diagrams, see BODY CONTROL COMPUTER - INTRODUCTION. Perform VERIFICATION TEST: VER-2A after each repair.

CAUTION: Always turn ignition switch to OFF position prior to disconnecting or connecting any module connector.

Ensure scan tool can communicate with Body Control Module (BCM). If BCM communication is not possible, see appropriate VEHICLE COMMUNICATIONS article. Using scan tool, select BODY SYSTEM, BODY COMPUTER, then SENSORS. Read IGNITION VOLTAGE. If scan tool displays battery voltage, go to next step. If scan tool does not display battery voltage, go to TEST 16A in appropriate VEHICLE COMMUNICATIONS article.
Turn ignition on. Using scan tool, select ELECTRO/MECHANICAL cluster. If scan tool displays NO RESPONSE, go to TEST 6A in appropriate VEHICLE COMMUNICATIONS article. If scan tool does not display NO RESPONSE, go to next step.
Using scan tool, select MONITOR, then PCI BUS ENGINE INFO. If scan tool displays NO RESPONSE, go to TEST 9A in appropriate VEHICLE COMMUNICATIONS article. If scan tool does not display NO RESPONSE, go to next step.

Using scan tool, select INSTRUMENT CLUSTER. Read DTCs (fault messages). See INSTRUMENT CLUSTER FAULT MESSAGE DIRECTORY table. If none of the following messages are displayed, go to next step.

INSTRUMENT CLUSTER FAULT MESSAGE DIRECTORY

Message Displayed

⁽¹⁾ Go To Test

EATX BUS COMM FAILURE

10A

SBEC BUS COMM FAILURE

AIR BAG BUS COMM FAILURE

ABS BUS COMM FAILURE

11A

BCM BUS COMM FAILURE

⁽¹⁾	See test listed in appropriate VEHICLE COMMUNICATIONS article.

Using scan tool, select BODY CONTROL MODULE, then READ DTCs. If scan tool displays FUEL LEVEL SENDING UNIT FAILURE, go to INSTRUMENT CLUSTER TEST 2A . If scan tool does not display FUEL LEVEL SENDING UNIT FAILURE, go to next step.
If scan tool displays DIMMING LEVEL SWITCH FAILURE, go to INSTRUMENT CLUSTER TEST 3A . If scan tool does not display DIMMING LEVEL SWITCH FAILURE, go to next step.
Identify problem(s) listed in INSTRUMENT CLUSTER DIAGNOSTIC TEST DIRECTORY table and perform indicated test(s).
If speedometer, tachometer or temperature gauges intermittently go to zero or to lowest point, select MONITOR, then ENGINE INFO using scan tool. While wiggling wiring harness and connectors, monitor scan tool. If scan tool displays NO RESPONSE, disconnect appropriate connectors and inspect terminals for corrosion or loose pushed out terminals. Repair as needed.

INSTRUMENT CLUSTER DIAGNOSTIC TEST DIRECTORY

Problem	Perform
All Gauges Not Operating	INSTRUMENT CLUSTER TEST 4A
One Gauge Not	INSTRUMENT CLUSTER TEST 5A
Odometer Malfunction	INSTRUMENT CLUSTER TEST 6A
Any Or All Warning Lights Malfunctioning	INSTRUMENT CLUSTER TEST 7A
PRNDL Not Malfunctioning	INSTRUMENT CLUSTER TEST 8A
Cluster And Panel Illumination Malfunction	INSTRUMENT CLUSTER TEST 9A