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Identifying Vehicle Equipment & System Problems

  1. Connect scan tool to Data Link Connector (DLC). DLC is a 16-pin connector located on left side of steering column, above brake pedal. Turn ignition on. If scan tool display is not blank, go to next step. If scan tool display is blank, go to appropriate test in VEHICLE COMMUNICATIONS article.
  2. Using scan tool, select BODY SYSTEM, then BODY COMPUTER. Scan tool will perform a CCD bus test. If scan tool displays BUS OPERATIONAL, go to next step. If scan tool displays NO RESPONSE, go to appropriate test in VEHICLE COMMUNICATIONS article. If scan tool displays any other message, go to appropriate test in VEHICLE COMMUNICATIONS article.
  3. Using scan tool, select READ DTCs. If any fault messages are displayed, go to FAULT MESSAGE IDENTIFICATION  table to identify which system is affected. Go to applicable test in appropriate DIAGNOSTIC TESTS section. If no fault messages are displayed, go to SYMPTOM TEST DIRECTORY  table for list of identified systems. Fault messages or symptoms are diagnosed using a scan tool and/or DVOM. These problems may occur separately or in various combinations. When diagnosing a system with many apparent problems, a sequence of tests may be required. After repairs, ensure problem(s) or failure(s) have been corrected by performing appropriate verification test.
FAULT MESSAGE IDENTIFICATION

Scan Tool Display Affected System (1)
BATTERY IOD DISCONNECT AT BCM (2)
BCM EEPROM CHECKSUM FAILURE (2)
BCM FLASH CHECKSUM FAILURE (2)
BCM J1850 BUS MESSAGE FAULTS - MESSAGES NOT RECEIVED (2)
BCM MATURED FAULT PRESENT (2)
DDM MESSAGE NOT RECEIVED (2)
MIC MESSAGE NOT RECEIVED BY BCM (2)
PCM MESSAGE NOT RECEIVED BY BCM (2)
PDM MESSAGE NOT RECEIVED BY BCM (2)
FOG LAMP RELAY CKT SHORTED HI Exterior Lighting
FOG LAMP RELAY CKT SHORTED LO/OPEN Exterior Lighting
HAZARD RELAY CKT SHORTED HI Exterior Lighting
HEADLAMP SW OPEN CKT Exterior Lighting
HEADLAMP SW SHORT TO GROUND Exterior Lighting
HIGH BEAM RELAY CKT SHORTED HI Exterior Lighting
LOW BEAM RELAY CKT SHORTED HI Exterior Lighting
LOW BEAM RELAY CKT SHORTED LO/OPEN Exterior Lighting
PARK LAMP RELAY CKT SHORTED HI Exterior Lighting
PARK LAMP RELAY CKT SHORTED LO/OPEN Exterior Lighting
ABS LAMP CKT SHORT (3)
ABS LAMP OPEN Instrument Cluster
ABS MESSAGE NOT RECEIVED BY MIC Instrument Cluster
ACM MESSAGE NOT RECEIVED BY MIC Instrument Cluster
AIRBAG LAMP DRIVER FAILURE (3)
AIRBAG LAMP OPEN Instrument Cluster
BCM MESSAGES NOT RECEIVED BY MIC Instrument Cluster
BRAKE LAMP CKT SHORT Instrument Cluster
BRAKE LAMP OPEN (3)
JTEC MESSAGE NOT RECEIVED BY MIC Instrument Cluster
SKIM MESSAGE NOT RECEIVED BY MIC Instrument Cluster
DIM SW OPEN CKT Interior Lighting
DIM SW SHORT TO GROUND Interior Lighting
LAMP FADE FAILURE SHORT TO BATT Interior Lighting
LOAD SHED FAILURE SHORT TO BATT Interior Lighting
PANEL LAMP DRIVER FAILURE Interior Lighting
AMBIENT TEMP Overhead Console
AMBIENT TEMP SENSOR CKT SHORT TO GND Overhead Console
COOLANT LEVEL SWITCH CIRCUIT OPEN Overhead Console
EVIC INTERNAL FAILURE (4)
EVIC NOT RECEIVING BUS MESSAGES Overhead Console
ACCESSORY DELAY RELAY SHORTED HI Power Top
ANTENNA FAILURE Vehicle Theft Security System (VTSS)
EEPROM FAILURE Vehicle Theft Security System (VTSS)
INTERNAL SKIM FAILURE (5)
PCM STATUS FAILURE Vehicle Theft Security System (VTSS)
ROLLING CODE FAILURE Vehicle Theft Security System (VTSS)
SERIAL LINK EXTERNAL FAILURE Vehicle Theft Security System (VTSS)
SERIAL LINK INTERNAL FAILURE (5)
TRANSPONDER COMMUNICATION FAILURE Vehicle Theft Security System (VTSS)
TRANSPONDER CRC FAILURE Vehicle Theft Security System (VTSS)
TRANSPONDER ID MISMATCH Vehicle Theft Security System (VTSS)
TRANSPONDER RESPONSE MISMATCH Vehicle Theft Security System (VTSS)
VIN MISMATCH Vehicle Theft Security System (VTSS)
WASHER FLUID SENSOR FAILURE Windshield Wiper
WIPER ON/OFF RELAY SHORTED HIGH Windshield Wiper
WIPER ON/OFF RELAY SHORTED LOW/OPEN CIRCUIT Windshield Wiper
WIPER PARK FAILURE Windshield Wiper
WIPER SWITCH MUX CKT OPEN Windshield Wiper
WIPER SWITCH MUX CKT SHORT TO GROUND Windshield Wiper
(1) Go to applicable TESTS section.
(2) Go to VEHICLE COMMUNICATIONS article.
(3) Replace instrument cluster circuit board.
(4) Replace vehicle information center module in overhead console.
(5) Replace SKIM and perform SKIM INITIALIZATION PROCEDURE  .
SYMPTOM TEST DIRECTORY

Suspected System Proceed To
Exterior Lights EXTERIOR LIGHTING SYMPTOM TESTS 
Instrument Cluster INSTRUMENT CLUSTER SYMPTOM TESTS 
Interior Lights INTERIOR LIGHTING SYMPTOM TESTS 
Power Door Locks POWER DOOR LOCK/REMOTE KEYLESS ENTRY (RKE) SYMPTOM TESTS 
Remote Keyless Entry (RKE) POWER DOOR LOCK/REMOTE KEYLESS ENTRY (RKE) SYMPTOM TESTS 
Power Top POWER TOP SYMPTOM TESTS 
Power Windows POWER WINDOW SYMPTOM TESTS 
Vehicle Theft Security System VEHICLE THEFT SECURITY SYSTEM SYMPTOM TESTS 
Windshield Wiper/Washer WINDSHIELD WIPER/WASHER SYSTEM SYMPTOM TESTS 
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