Diagnostic Procedure Sequence
NOTE:
Following diagnostic procedure sequence should be followed for diagnosing module communications network.
- Verify customer's original problem. Inspect vehicle for any obvious electrical component wiring or connector damage.
- Inspect terminals in 16-terminal Data Link Connector (DLC) for damage. See Fig 1 . The DLC is a located below driver's side of instrument panel, to the right of steering column. If terminals are okay, go to next step. If terminals are damaged, repair as necessary and proceed to next step.
- Ensure transmission is in Park. Ensure all controls and switches are in the OFF position. Connect New Generation Star (NGS) scan tester to Data Link Connector (DLC).
- Check that all doors, hood and trunk are fully closed. Perform proper hook-up procedure and vehicle selection for scan tester. See EQUIPMENT HOOK-UP
.NOTE: DO NOT touch any handle or switch that may produce a module input unless instructed to do so by the scan tester. Do not sit in driver seat while performing diagnostics.
- Perform data link diagnostics. See DATA LINK DIAGNOSTICS .
- Retrieve continuous Diagnostic Trouble Codes (DTCs) from selected module(s). See RETRIEVING DIAGNOSTIC TROUBLE CODES . Record all continuous DTCs.
- Clear continuous DTCs from selected module. See CLEARING DIAGNOSTIC TROUBLE CODES .
- Perform On-Demand Self-Test on selected module. See ON-DEMAND SELF-TEST. Record all DTCs obtained when performing On-Demand Self-Test.
- If no DTCs were obtained when retrieving continuous DTCs or performing On-Demand Self-Test, continue diagnosis by symptom, as the problem is not related to module communications network.
- If DTCs were obtained when retrieving continuous DTCs or performing On-Demand Self-Test, proceed to DIAGNOSTIC TROUBLE CODE (DTC) DEFINITIONS for proper DTC testing procedure. DIAGNOSTIC TROUBLE CODE (DTC) DEFINITIONS are listed after TESTING in this article.