The 1997 civic I have needs the battery replaced. I have heard that if you disconnect the battery and don't have a special code then things may not work right on the radio. Is this true? What is the proper procedure for replacing the battery? Thanks

 

Yeah, you may have a problem with that. I'm not sure what the best solution is but you could go to the dealer to unlock the unit.
Try searching this forum too, this has been asked a lot of times I think.