Engine Controls - System/Component Tests 4.6L: Introduction: Notes

Before testing separate components or systems, perform procedures in the BASIC TESTING - 4.6L article. Since many computer-controlled and monitored components set a trouble code if they malfunction, also perform procedures in the appropriate TESTS W/CODES - EEC-IV 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 appropriate wiring diagram in the WIRING DIAGRAMS article in the ENGINE PERFORMANCE section.

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