Thank you for allowing me to assist you, my name is Joe and I will be happy to assist you with your concern today.
Try the basics like 0000, 1234, 4321, 1111, 9999 are the most common. If not then I will need the make and model number, in most cases you will have 2 options which are visit a local car audio shop that deals in that brand which can unlock it or contacting the manufacture directly and proving ownership. Both usually do charge a fee, in some cases they may not charge, in most cases there is NO way around this esp aftermarket radios. A factory radio you will need to contact your local dealership which can provide the code. Now there is a chance in the owners manual (car or radio) that they wrote the code down.
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