Engine Controls - Tests W/O Codes: Introduction

Before diagnosing symptoms or intermittent faults, perform steps in the following articles;

Use this articles to diagnose driveability problems existing when a hard fault code is not present.

NOTE: Some driveability problems may have been corrected by manufacturer with a revised computer control unit. Check with manufacturer for latest computer 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 a soft (intermittent) trouble code was present, but no problem was found during self-diagnostic testing.

NOTE: For specific testing procedures see appropriate articles;

For ES300 SYSTEM/COMPONENT TESTS

For LS400 SYSTEM/COMPONENT TESTS

For ES300 ADJUSTMENTS

For LS400 ADJUSTMENTS

For ES300 SPECIFICATIONS

For LS400 SPECIFICATIONS