Engine Controls - System & Component Testing 7.4L: Introduction
Before testing separate components or systems, perform BASIC TESTING - 7.4L article. Since many computer-controlled and monitored components set a trouble code if they malfunction, also perform procedures in TESTS W/CODES - 7.4L 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 - 7.4L
to isolate wiring harness shorts or opens.