I just bought a used 2005 S2000 and I'm having some issues with my alarm and hopefully one of you can help. Here is some background on the issue:

2005, 24k miles, only one key came with the car (no fob). I went to a honda dealership and got a a spare key along with a FOB so that I could lock/unlock my doors. I programmed the FOB myself using info I found online and the FOB works fine. My doors unlock and the trunk opens fine. However, here is my ISSUE:

If i unlock the doors and then immediately pop the trunk using the FOB the car FREAKS out. The alarm goes off (sound comes from car horn) and it takes about a minute to stop it. I have to close the trunk and then hold down the lock button on the fob button a few tiems to disable it. I also tried unlocking the car with the fob and then immidiately popping the trunk using the button in the car and the alarm STILL goes off. Has anyone had an issue like this before?

thanks

 

Sounds like the car has the optional factory alarm and the remote you bought was for just keyless. When you hit unlock its not dissarming the system. Trade the key fob in for the one for the optional alarm fob. Same programming.