I have 1990 Sunbird with a factory radio that is displaying "LOC" and won't turn on or do anything. It was fine until the battery died and I jump started it with a car starter/battery charger. I've had both pieces (the head unit and the "brain box") out of the car and disconnected from power for days and this never happened. I know the first thing that will come to mind is that LOC = Theftlock. Problem is, I don't think GM used Theftlock on these radios back then. Anybody have any clues on how fix this?

It means your radio is dying, and you should get a new one. That happened more and more until it died on mine.

Hmm...I did the ol' remove all power from the radio overnight trick and it came back to life. It wouldn't surprise me if it were dying...but it working for now so I'll worry about it later.

Thanks