Engine Controls - System/Component Tests: Introduction

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

For 3.0L, see TESTS W/CODES - MOTRONIC 5.2 SYSTEM.
For 2.3L, see TESTS W/CODES - TRIONIC SYSTEM.

NOTE: Testing of individual components does not isolate possible shorts or opens. Unless stated otherwise in testing procedures, perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) with minimum 10-megohm input impedance. Use ohmmeter to isolate wiring harness shorts or opens.