What is GM TheftLock?

TheftLock is the anti-theft feature built into many General Motors factory radios — Chevrolet, GMC, Buick, Cadillac, Pontiac, Oldsmobile, Hummer and more. It's designed to make a stolen radio useless by locking it with a security code whenever the radio loses power.

When TheftLock activates

If the battery dies or is disconnected, the radio fuse is pulled, or the radio is removed, the unit locks and the display shows LOC (locked) — or INOP if too many wrong codes have been tried. The radio won't play until the correct unlock code is entered.

How to read your TheftLock serial number

1. Turn the ignition ON — the radio displays LOC.
2. Press and hold presets 2 & 3 (or 1 & 4) for about 10 seconds.
3. A three-digit number appears; press AM/FM for the second three digits.
4. Together they form your serial number (some Saturn/Geo units show all four digits at once).

Getting your unlock code

Send us that serial number and we'll retrieve your GM unlock code. Then, with the ignition on, you enter it using the HR and MN buttons. If the radio went to INOP, leave the ignition on for an hour to reset to LOC first.

Note: GM RDS radios from 2003 and newer use a different system we don't support — but the vast majority of GM TheftLock radios we unlock daily.

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