I have been extracting OBD-II DATA from UART board (ELM327) on my TOYOTA INNOVA. It responded correctly few weeks before and gave all supported sensor values. But now, for every response, ECU responds "7F 01 11". Please tell me what exactly this output means and how to get rid of this problem
7F = general fail response.
11 = Service Not Supported.
That is the meaning. It's odd that it was working before. Ultimately, it could be the device that you are using to read the codes is defective.