On-Board Diagnostic II (OBD-II) System Check: Description

The On-Board Diagnostic II (OBD-II) System Check is the starting point for any driveability complaint diagnosis. Before any DTC(s) are retrieved, perform a visual underhood inspection checking battery and grounds for clean and tight connections. Check for poor connections or damage to wiring harness and electrical connectors. Check for corroded terminals or corrosion build-up on any connection. Repair as necessary. The OBD-II system check is an organized approach to identifying problems created by an electronic engine control system malfunction.

Use of Tech 2 scan tool is required to perform ON-BOARD DIAGNOSTIC II (OBD-II) SYSTEM CHECK. To reprogram EEPROM or to program PCM after it has been replaced, see COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION section.