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General Information

WARNING: This page is about a different car, the 2002 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.

A large number of ECU controlled systems are used in the Sequoia. In general, the ECU controlled system is considered to be a very intricate system requiring a high level of technical knowledge and expert skill to troubleshoot. However, the fact is that if you proceed to inspect the circuits one by one, troubleshooting of these systems is not complex. If you have adequate understanding of the system and a basic knowledge of electricity, accurate diagnosis and necessary repair can be performed to locate and fix the problem. This information is designed through emphasis from the above standpoint to help service technicians perform accurate and effective troubleshooting, and is compiled for the following major ECU controlled systems.

The troubleshooting procedure and how to make use of it are described in the articles linked to the Troubleshooting table.

Troubleshooting Table

System See
Engine SELF-DIAGNOSTICS
Automatic Transmission DIAGNOSIS - A340E & A340F
ABS with EBD/TRAC/VSC System DIAGNOSTICS - SEQUOIA
Supplemental Restraint System AIR BAG RESTRAINT SYSTEMS
Cruise Control System CRUISE CONTROL SYSTEMS
Engine Immobilizer System ENGINE IMMOBILIZER SYSTEM
Body Control System BODY, CAB CONTROL SYSTEMS - DIAGNOSTICS
Driver Door Control System DRIVER DOOR CONTROL SYSTEM - DIAGNOSTICS
Passenger Door Control System PASSENGER DOOR CONTROL SYSTEM - DIAGNOSTICS
Back Door Control System BACK DOOR CONTROL SYSTEMS - DIAGNOSTICS
Air Conditioning System HVAC - DIAGNOSTICS