I have the same problem, whilst changing the video player for a dvd player I have shorted something but after checking all the fuses I can find, nothing. The power supply to the video gives a couple of volts but when you switch the power on via the remote pointing at the headrests it gives 12v, so off that came my dvd, only prob is it no longer gives 12v. In fact it doesn't switch the screens on at all now. HHHELLLLLLLLLLLLLLLPPPPPPPP please. ;)