Smart & Connected Life > Connected Car Tech 81 81 people found this article helpful What Is a Car Radio Code? Keep those numbers handy By Jeremy Laukkonen Jeremy Laukkonen Writer Shoreline Community College Jeremy Laukkonen is automotive and tech writer for numerous major trade publications. When not researching and testing computers, game consoles or smartphones, he stays up-to-date on the myriad complex systems that power battery electric vehicles . lifewire's editorial guidelines Updated on July 12, 2021 In This Article Expand Jump to a Section Finding Your Car Radio Code Look in the Owner's Manual Check Manufacturers' Sites Call Your Dealer Pay for a Service Entering the Code Battery Memory Keeper Devices Trending Videos Close this video player A car radio code is a short string of numbers associated with a security feature found in some head units. Its purpose is to prevent theft by rendering a stolen head unit useless when it's disconnected from the battery. However, this feature also kicks in if your battery dies. In either case, you must enter the code to get the head unit working again. The typical radio will flash "CODE" to indicate this. Finding Your Car Radio Code There are a few ways to locate a car radio code, but here are the main ones, in descending order of complexity and cost. Look in the Owner's Manual In some cases, you might find the car radio code in the owner's manual. This isn't an especially secure place for it, given that most people keep their manuals in their vehicles, but some manuals have a space for it. If you bought your car used, the previous owner might have entered it there. Check Manufacturers' Websites Check the sites of your automaker and the stereo manufacturer. Companies sometimes keep online databases of car radio codes. Entering info such as your vehicle identification number (VIN) or the radio's serial number might return the code you're looking for. In addition to OEM databases, a handful of free databases offer codes for various types of radios. Call Your Dealer Regardless of which dealer you bought your car from, one should be able to help. Have the make, model, year, and VIN of your vehicle handy in addition to the serial and part numbers of the radio. Pay for a Service If none of those options works, you’ll need to pay for a local or online service that has access to a database of car radio codes. Typically, they need the make and model of your vehicle, the brand and model of the radio, and the radio's part and serial numbers. Once you find your code, jot it down and keep it somewhere safe and easily accessible. Entering the Code The procedure for entering the car radio code is specific to the make and model of the stereo. In most cases, use the volume or tuner knobs or buttons to select numbers, and then click the knob or push another button to advance. Some late-model autos and sound systems require you to press a combination of buttons rather than enter a code. Be careful entering codes; too many tries might lock you out. Then, you'll have to complete a reset procedure. In some cases, you must disconnect the battery again and leave it disconnected for a while. In other cases, you must turn on the ignition (but not start the engine), turn on the radio, and wait for a period of time. The procedure varies, so check the owner's manual for your vehicle. Battery Memory Keeper Devices Memory keeper (or keep alive) devices prevent the radio from requiring a code after the battery has been disconnected. These devices typically plug into the cigarette lighter and provide limited power to the electrical system while the battery is disconnected. Although these devices typically work fine, they pose a danger to the electrical system. If you plug one of these devices in when replacing a battery, for example, the positive battery cable contacting any ground (for example, the negative battery cable, frame, or engine) will cause a short. There might be additional precautions to be aware of, so read the instruction manual carefully. Was this page helpful? Thanks for letting us know! Get the Latest Tech News Delivered Every Day Subscribe Tell us why! Other Not enough details Hard to understand Submit