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Home >> Isuzu >> 1999 >> Trooper Part Time >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics (Introduction) >> On-Board Diagnostic II (OBD-II) System Check >> Description
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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. The OBD-II system check is an organized approach to identifying problems created by an electronic engine control system malfunction. 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.

Use of Tech 2 scan tool is required to perform ON-BOARD DIAGNOSTIC II (OBD-II) SYSTEM CHECK  .

NOTE: To identify component terminals and wire colors referenced in testing, see appropriate wiring diagram in WIRING DIAGRAMS article.