How To Proceed With Troubleshooting
WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.
HINT:
The ECU of this system is connected to the mutiplex communication system. Therefore, before starting troubleshooting, make sure to check that there is no trouble in the mutiplex communication system.
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