Section 249 (Engine Controls - System & Component Testing): Introduction

WARNING: This page is about a different car, the 2003 Cadillac Seville and 2003 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

Before testing separate components or systems, follow proper workflow. See DIAGNOSTIC STARTING POINT - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 4.6L DEVILLE & SEVILLE article. If no Diagnostic Trouble Codes (DTC) are present and a no-start condition exists, proceed to NO-START DIAGNOSIS in BASIC DIAGNOSTIC PROCEDURES - 4.6L DEVILLE & SEVILLE article. If no DTCs are present and a driveability condition exists, proceed to SYMPTOMS in TROUBLE SHOOTING - NO CODES - 4.6L DEVILLE & SEVILLE article for diagnosis by symptom (i.e. ROUGH IDLE, ENGINE STALLS, etc.).

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