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Engine Control System & Engine Component Tests: Introduction

Before testing separate components or systems, perform procedures in BASIC DIAGNOSTIC PROCEDURES article. Since many computer-controlled and monitored components set a Diagnostic Trouble Code (DTC) if they malfunction, also perform procedures in CHRYSLER CORP. - SELF-DIAGNOSTICS - JEEP, TRUCKS & RWD VANS article.

NOTE: Testing individual components does not isolate possible short or open circuits. Unless stated otherwise in test procedure, perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) having a minimum 10-megohm input impedance. Use ohmmeter to isolate wiring harness short or open circuits.