Engine Controls - System & Component Testing - 3.4L: Introduction

Before testing separate components or systems, perform appropriate procedures in BASIC TESTING - 3.4L article. Since many computer-controlled and monitored components set a Diagnostic Trouble Code (DTC) if they malfunction, also perform procedures in TESTS W/CODES - 3.4L article.

NOTE: Testing individual components does not isolate short or open circuits. 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 to isolate shorted or open wiring harness.

NOTE: For wiring diagrams not shown in testing procedures, see WIRING DIAGRAMS - 3.4L article.

NOTE: In following tests, circuit diagrams and illustrations are courtesy of Ford Motor Co.