General Information

INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: GENERAL INFORMATION

GENERAL INFORMATION
- A large number of ECU controlled systems are used in the LEXUS IS250/350. In general, ECU controlled systems are considered to be very intricate, requiring a high level of technical knowledge to troubleshoot. However, most problem checking procedures only involve inspecting the ECU controlled system's circuits one by one. An adequate understanding of the system and a basic knowledge of electricity is enough to perform effective troubleshooting, accurate diagnoses and necessary repairs.
- FOR USING THE TECHSTREAM

- Before using the Techstream, read the Techstream operator's manual thoroughly.
- If the Techstream cannot communicate with the ECU controlled systems when the Techstream is connected to the DLC3 with the ignition switch on and the Techstream turned on, there is a problem on the vehicle side or the Techstream side.
1. If communication is normal when the Techstream is connected to another vehicle, inspect the diagnosis data link line (Bus (+) line) or ECU power circuit of the vehicle.
2. If communication is still not possible when the Techstream is connected to another vehicle, the problem is probably in the Techstream itself. Perform the Self Test procedures outlined in the Techstream operator's manual.