No prob, I had the same issue while trying to do my emissions test before I figured out what the problem was. For some reason if that wire is connected in the harness the wire that it matches up to on the car side (called the "k" wire) will cause your OBD to cut off. The wire coming from the radio that is usually hooked up is either the amp turn-on or power antenna. Either way, you won't need these to be hooked up since there is no power antenna and the amp turn-on won't even get the back speakers to play, gotta splice some RCAs onto em and plug 'em in to the "Rear" pre-out in the head unit. I guess that sending 12 volts to that wire when the radio turns on interrupts the constant supply to the OBD plug.