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Engine Controls - System & Component Testing: Introduction

CAUTION: When battery is disconnected, radio will go into anti-theft protection mode. Obtain radio anti-theft protection code from owner prior to servicing vehicle.
NOTE: Testing individual components does not isolate shorts or opens. Perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance unless otherwise instructed in test procedure. Use ohmmeter to isolate wiring harness shorts or opens.

Before testing separate components or systems, perform preliminary inspection. See BASIC DIAGNOSTIC PROCEDURES article.

Many computer-controlled and/or monitored components set a Diagnostic Trouble Code (DTC) if they malfunction. In this event testing is incorporated in self-diagnostics testing. For testing procedures, see appropriate SELF-DIAGNOSTICS article. For systems and components not covered in this article, use self-diagnostics testing procedures.

For aid in locating components, see component location illustrations in REMOVAL, OVERHAUL & INSTALLATION article.