HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS A large number of ECU controlled systems are used in the TOYOTA SUPRA. 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 manual is designed through emphasis of the above standpoint to help service technicians perform accurate and effective troubleshooting, and is compiled for the following major ECU controlled systems: Repair Manual | System | Page Vol. 1 1. 2JZ–GE Engine | EG–381 2JZ–GTE Engine | EG–487 Vol. 2 2. A340E (2JZ–GE) Automatic Transmission | AT1–31 A340E (2JZ–GTE) Automatic Transmission | AT1–31 3. Anti–Lock Brake | BR–51 4. Traction Control | BR–123 5. Supplemental Restraint System | RS–41 6. Theft Deterrent and Door Lock System | BE–142 7. Cruise Control | BE–163 8. Air Conditioning | AC–13 The troubleshooting procedure and how to make use of it are described on the following pages.