How to Unlock Your Locked GM Theftlock Radio

Finding Your Radio Identification Code

Put your key in the ignition and turn on your radio. Start your vehicle like normal, or turn the key until it's in the “On” or “Accessory” position. Then, press the power button on the radio’s volume dial to turn on the radio. The digital display will read “LOC” if the radio is locked. If you don’t see the letters “LOC” but your radio isn’t working, the issue may lie elsewhere. Take your car to a qualified GM mechanic or car radio technician to have them diagnose the source of the problem. GM Theftlock radios are designed to lock up automatically when the vehicle’s battery dies or becomes disconnected, though an electronic malfunction could also cause the Theftlock function to activate.Tip: If the letters “RDS” appear on the display, it won’t be possible to unlock your radio yourself, as GM doesn’t offer retrieval codes for RDS radio units. In this case, you’ll need to visit a licensed GM dealership to have them reset your radio manually.

Grab a piece of paper and something to write with. Unlocking your Theftlock radio will require you to enter a unique 4-digit numerical code. Before you can do this, however, it will be necessary to write down two separate 3-digit numbers, which you’ll get by punching a series of buttons on the radio’s interface. You’ll be jotting down 3 sets of numbers in all, so make sure there’s plenty of room on your scrap paper. Try not to waste any time recording each set of numbers as they appear. Most GM Theftlock radios only give you 10-15 seconds to perform each step in the process before the display resets itself.

Press and hold presets 1 and 4 until a 3-digit number appears on the display. You may have to hold both buttons for up to 10 seconds. When the numbers finally appear, write them down quickly and accurately. They are the first 3 digits of your radio's identification code. If your radio doesn’t have 4 preset buttons, press and hold presets 2 and 3 instead.

Hit the AM/FM button to get the second half of your radio identification number. After you press the button, 3 more numbers will pop up on the radio’s display. These are the last 3 digits of your radio’s identification code. Write these numbers down alongside the first 3 digits. Make sure the 2 sets of numbers are in the right order. If you enter your radio identification number incorrectly, your attempt to unlock your radio will fail. You’ll need to confirm this 6-digit radio identification code with GM over the phone in order to unlock your radio.

Phoning in for Your Radio Retrieval Code

Dial 1-800-537-5140 to connect with GM’s toll-free radio hotline. Once you’re connected, you’ll be asked to provide your vehicle’s radio identification number, along with a special dealer access code. You’ll then be rewarded with a 4-digit retrieval code, which will allow you to unlock your radio. This is an automated line, so you won’t have to wait to talk to a live human being. You can call GM’s radio hotline for assistance at any time, day or night.

Enter the numbers “106010” when prompted for a dealer access code. This is the most common code used by GM personnel to reset locked Theftlock radios. Key in each number carefully, then hit the # sign to send your request through. Under normal circumstances, a locked Theftlock radio must be reset by a licensed GM dealer, who uses a special code known only by dealership personnel. By entering the code yourself, you can avoid the trouble and expense of paying to have your vehicle’s radio unlocked at the dealership.Tip: GM has multiple dealer access codes, some of which are assigned to different dealerships for different vehicles. If the first code doesn’t work, hang up and try again using one of the following codes: 620529, 139010, 206053, or 202108.

Punch in your vehicle's 6-digit radio identification number when instructed. Refer back to the two 3-digit numerical codes you wrote down earlier and enter them in a single unbroken sequence using your phone's keypad. Once you’ve done that, press the * sign and prepare to receive your radio retrieval code. Remember to read the numbers from left to right, and be careful not to accidentally include any other numbers or symbols. You should make a total of 7 button presses when it’s all said and done.

Write down the 4-digit radio retrieval code as it’s recited to you. The automated voice on the other end of the line will only repeat the code once, so listen closely and have your pen and paper ready to record the numbers neatly and precisely. You now have all the information you need to unlock your radio, so you can hang up the phone. If you don’t catch one or more numbers of the retrieval code, you’ll have no choice but to start the call over from the beginning.

Using Your Radio Retrieval Code to Unlock Your Radio

Press the hour button on the radio until the first 2 numbers of the code appear. With each button press, the number displayed will increase by 1. Continue ticking off the numbers in the hour position until they match the first half of your radio retrieval code. If the first 2 digits of your radio retrieval code are “10,” for instance, you would need to push the hour button 10 times. On most Theftlock radios, you’ll find the time set buttons in the lower righthand corner of the radio interface.

Hit the minute button to bring up the last 2 digits of your retrieval code. To finish entering the code, do the same thing that you just did to put in the first 2 digits, only this time with the numbers in the minute position. Double-check that each number of the code is correct before proceeding. Holding the minute button will cycle through the numbers automatically so you don’t have to keep pressing it over and over again.

Press the AM/FM button to unlock your radio. The display should now read, "SEC," meaning that the radio has been successfully unlocked. Switch on the radio and specify your audio input of choice and it should begin playing as normal. It’s as simple as that! You can repeat this process to resume use of your Theftlock radio any time it locks up unexpectedly. If your radio is still locked or refusing to cooperate after you’ve entered your radio retrieval code, your best bet is to schedule an appointment at a GM dealership to have it looked at by a professional.

Leave your battery on for 1 hour to clear an “INOP” message. Some Theftlock radios will shut down altogether if you attempt to enter an incorrect radio retrieval code too many times. When this happens, the display will read “INOP,” short for “inoperable.” All you can do at this point is leave the key turned to the “On” position for a full hour and wait for the message to go away on its own. It’s important to record and enter your radio retrieval code correctly the first go-around to save yourself time, energy, and battery power.