Vehicle On-Board Diagnostic System Check

The powertrain diagnostic system check determines:

• If Malfunction Indicator Light (MIL) operates.
• If PCM is operating and can recognize a fault.
• If any DTCs are stored.

1. Connect scan tool to 16-pin DLC located under left side of instrument panel. See Figure . If scan tool does not power up, see SCAN TOOL DOES NOT POWER UP in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. If scan tool powers up, go to next step.
2. Attempt to establish communications, read and record DTCs from BCM, SDM, PCM and ABS (if equipped) modules. If scan tool communicates with BCM, go to step  4 . If scan tool does not communicate with BCM, go to next step.
3. If scan tool communicates with SDM, go to step  5 . If scan tool does not communicate with SDM, see NO COMMUNICATION ON CLASS-2 DATA LINK in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
4. If any DTCs are set in BCM, see appropriate test under DIAGNOSTIC TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. If no DTCs are set in BCM, go to next step.
5. If any DTCs are set in SDM, see appropriate test under DIAGNOSTIC TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. If no DTCs are set in SDM, go to next step.
6. If DTCs are set in PCM, see DIAGNOSTIC TROUBLE CODE DEFINITIONS  . If no DTCs are set in PCM, go to next step.
7. If scan tool communicates with EBTCM, go to next step. If scan tool does not communicate with EBTCM, see NO COMMUNICATION WITH EBTCM in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
8. If DTCs are present in EBTCM, see appropriate ANTI-LOCK/TCS article in BRAKES. If no DTCs are present in EBTCM, go to next step.
9. If engine starts and runs, diagnostic system check is complete. If problem exists, observe scan tool data and/or refer to symptom in appropriate TROUBLE SHOOTING - NO CODES article. If engine does not start and run, see appropriate BASIC DIAGNOSTIC PROCEDURES article.