| The radio code in most Honda's is written either in the handbook or on a card that is with the handbook. Another thing that has been done is affixing it to a sticker and placing the sticker somewhere in the car like on the side of the glove box when the glove box is open or on the inside of the fuse panel lid. Finding it can be an adventure in itself. I have even heard of individuals finding it in the engine compartment and under the rear hatch. Unfortunately, the sticker is not labelled to let you know that it is the radio code. It usually consists of 2 sets of numbers and sometimes they are proceeded with a letter. The second number will consist of 5 numbers and may or may not be preceeded with a letter. The 5 digits are the radio unlock code. If you insert it 3 times incorrectly it will lock you out. If that happens you either drive for 1 hour with the radio on which will clear it or unhook your battery for a couple of minutes.
If you can't find the code card/sticker then you need to do this. With the radio off you need to hold in the #1 and #6 buttons and then turn the radio on. It will display 2 numbers (usually proceeded with a letter such as C1234 D4567). Write these numbers down. The numbers without the letters is the serial number. The example above would result in the serial number being 12344567. If that does not work, you must remove the radio and retrieve the serial number from the tag affixed to the radio. Once you have the serial number, call a Honda Dealer and ask for the service department. Give them the serial number and they can retrieve the number from their database.
If they give you any hassle call a different Honda Dealer. I called the first one and they wanted me to bring in all kinds of ID plus the title to prove I owned the car before they would release it. I was on temporary tags so I did not have my title back yet. I called a second one and they gave me the code over the phone, no questions asked. | 
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