However, this feature also kicks in if yourbattery 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.
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If you bought your car used, the previous owner might have entered it there.
Check Manufacturers' Websites
Check the website of your automaker and the stereo manufacturer.
Companies sometimes keep online databases of car radio codes.
In addition to OEM databases, a handful of free databases offer codes for various types of radios.
Once you find your code, jot it down and keep it somewhere safe and easily accessible.
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.
The procedure varies, so check the owner’s manual for your vehicle.
These devices typically plug into thecigarette lighterand 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.
There might be additional precautions to be aware of, so read the instruction manual carefully.
