Section 24 (Engine Controls - Basic Diagnostic Procedures): Introduction

WARNING: This page does not describe the selected car, but rather 34 other vehicles, including the 2001 BMW Z8, 2001 BMW Z3, 2001 BMW X5, 2001 BMW M5, and 2001 BMW M3. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Vehicles are equipped with an OBD-II diagnostic system, with an OBD-II Data Link Connector (DLC). See SELF-DIAGNOSTICS article.

The following diagnostic steps will help prevent overlooking a simple problem. This is also where to begin diagnosis for a no-start condition. The first step in diagnosing any driveability problem is verifying the problem with a test drive under the conditions the problem reportedly occurred.

Before entering self-diagnostics, perform a careful and complete visual inspection. Most engine control problems result from mechanical breakdowns, poor electrical connections or damaged/misrouted vacuum hoses. Before condemning the computerized system, perform each test listed in this article.

NOTE: Perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure.