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Engine Control System Self-Diagnostics: Introduction

NOTE: This article applies only to the gasoline engine used in this vehicle and does not apply to the hybrid vehicle control system which consists of A/C motor and high-voltage system. For diagnosis of the hybrid vehicle control system, consult authorized dealer.
WARNING: Read service precautions before proceeding with service procedure. See SERVICE PRECAUTIONS .
NOTE: Before performing testing procedures, check for any related Technical Service Bulletins (TSBs).

To properly diagnosis 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 - 4-CYLINDER . 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.).