Engine Controls - Self-Diagnostics (QG18DE): Introduction

To properly diagnose and repair this vehicle, follow TESTING PROCEDURE  under SELF-DIAGNOSTIC SYSTEM. If no Diagnostic Trouble Codes (DTC) are present and a no start condition exists, proceed to BASIC DIAGNOSTIC PROCEDURES article and perform PRELIMINARY INSPECTION & ADJUSTMENTS . If no DTCs are present and a driveability condition exists, proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e., ROUGH IDLE, ENGINE STALLS, etc).