I have a 2000 Disco II with the 4.0 eng. Iv'e been getting code p01540 (bank 2 sensor 1) I replace 02 sensor and got same code. I brought it to my mechanic and he found that the problem was a bad ground inside the PCM. He tried soldering inside the PCM to fix the ground but couldn't fix it. I would like to know if there is anything I can do to fix the problem our do I have to replace the PCM. If I get a PCM with the same numbers will it still have to be programmed?