Section 17 (Engine Controls - Basic Diagnostic Procedures): Introduction
WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 2002 Mazda Tribute, 2002 Mazda Protege5, 2002 Mazda Protege, 2002 Mazda Millenia, and 2002 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
When battery is disconnected, vehicle computer may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES
article in GENERAL INFORMATION before disconnecting the battery.
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 customer's complaint 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.