If you have the factory radio in that car, I think you need to figure out the radio code before unhooking the battery or your radio/security feature will give you problems. This is one thing I need to figure out on my 2000 civic. Anybody know how to get the radio code?
If you have never programmed it, or a previous owner never programmed it, the factory default code is in your owners manual. There will also be information on how to check / set the code.