Your GM radio is showing LOC or LOCKED and won't play. The factory Theftlock anti-theft system has activated and needs its unlock code.
LOC, LOCKED and THEFTLOCK are all the same message across GM's brands — Chevrolet, GMC, Buick, Cadillac, Pontiac, Oldsmobile and Saturn all use the same Delco-based system. It activates whenever the radio loses power and stays locked until the correct factory code is entered.
Almost always a dead or disconnected battery, a jump start, or a blown fuse — the lock can't tell that from a theft, so it plays it safe every time.
GM's method is different from most brands: the code goes in using the HR and MN (hour and minute) buttons rather than the station presets, stepping the digits up until they match.
Most GM radios carry a serial number printed on the unit, and on some the serial can be read from the display by holding presets 1 and 4. Send us that serial number (or VIN where the order form asks for it) and we'll match it to the factory code.
Standard delivery is usually within the hour, Express goes to the top of the queue, and we're open 7 days a week.
