Engine Controls - Self-Diagnostics: Introduction

To properly diagnose vehicle, vehicle manufacturer recommends use of Volkswagen Audi Group Scan Tool (VAG 1551) and Test Box (VAG 1598). All voltage and continuity tests should be performed with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless specifically stated different in testing procedures. Ensure ignition switch is in OFF position when performing resistance tests.

Perform a visual inspection, see VISUAL INSPECTION  . If no faults are found while performing visual inspection, proceed with SELF-DIAGNOSTICS. See SELF-DIAGNOSTIC SYSTEM  . If no Diagnostic Trouble Codes (DTCs) are present, proceed to TROUBLING SHOOTING - NO CODES article for diagnosis by symptom (e.g., NO START, ROUGH IDLE, ENGINE STALLS, etc.).