Volvo Radio Question

I have a 1991 Volvo wagon 245. The radio plays for like three minutes and then ask for some sort of code. What is this? I have no code and the dealer wants me to take it in so they can charge me to fix it. Can I fix this myself? Please help with this situation. Thanks in advance.

Was the battery recently disconnected, or had it gone dead? The radio is probably equipped with an anti-theft feature. If the radio loses power, the user (or thief) must enter the correct code before it will operate again. The code might have been programmed by the previous owner, or it could have been set by the factory---I'm not sure how the Volvo radios work. Maybe if you do some searching around the internet, you'll find the secret to getting around the code. Or get friendly with one of the dealer techs and ask him if he'll do it cheaper if you pay him cash.