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Engine Controls Self-Diagnostics - 3.5: Introduction

NOTE: This article also applies to Infiniti QX4. For QX4 coverage, refer to Pathfinder, unless otherwise indicated.
NOTE: Electronic Concentrated Control System (ECCS) control module is referred to as Engine Control Module (ECM).

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed with self-diagnostics. Using scan tool, review and record all DTC and freeze-frame information available. If no DTCs are present after entering self-diagnostics, proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.).