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Engine Controls - System & Component Testing - 5.7L: Introduction

Before testing separate components or systems, perform BASIC TESTING - 5.7L article. Since many computer-controlled and monitored components set a trouble code if they malfunction, also perform procedures in TESTS W/CODES - 5.7L article.

NOTE: Testing individual components does not isolate shorts or opens. Perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use ohmmeter and refer to WIRING DIAGRAMS - 5.7L to isolate wiring harness shorts or opens.