what does the ECU-B effect??

Hello, You likely have a bad relay that is stuck closed. This will provide power to a few different control modules on the vehicle at all times, and that will certainly cause your issue. A real easy way to check is to pull IG1 relay and the ACC relay. One of them will likely shut the light off as well. The service manual will have the wiring schematic so you can verify other portions of the system as well.