LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2003 >> Matrix Base, FWD, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 19 (Engine Control System Trouble Shooting - No Codes) >> Introduction
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Section 19 (Engine Control System Trouble Shooting - No Codes): Introduction

WARNING: This page does not describe the selected car, but rather 16 other vehicles, including the 2002 Toyota Tundra, 2002 Toyota Tacoma, 2002 Toyota Sienna, 2002 Toyota Sequoia, and 2002 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Before using Trouble Shooting - No Codes article, check for any related Technical Service Bulletins (TSBs) that may apply.

Before diagnosing symptoms or intermittent faults, follow proper workflow. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article. If no Diagnostic Trouble Codes (DTC) are present and a no start condition exists, proceed to appropriate BASIC DIAGNOSTIC PROCEDURES article. If no DTCs are present and a driveability condition exists, diagnosis by symptom (i.e., ROUGH IDLE, ENGINE STALLS, etc.).

NOTE: Some driveability problems may have been corrected by manufacturer with a revised Engine Control Module (ECM). Check with manufacturer for latest ECM application.

Symptom checks can direct the technician to malfunctioning component(s) for further diagnosis. A symptom should lead to a specific component, system test or adjustment.

Use intermittent test procedures to locate driveability problems that do not occur when the vehicle is being tested. These test procedures should also be used if an intermittent diagnostic trouble code was present, but no problem was found during self-diagnostic testing.