Engine Control - System & Component Testing - Except S40 & V40: Introduction

Before testing separate components or systems, perform procedures in BASIC DIAGNOSTIC PROCEDURES article. Since all monitored components set a Diagnostic Trouble Code (DTC) if they malfunction, see appropriate SELF-DIAGNOSTICS article.

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