While contemplating replacing the stock HU in my 98 Civic a couple years ago, I found in the owner's manual that removing the stock HU would remove the stock keyless entry function, as this function is controlled my the HU. I ended up keeping the stock HU.

As I'm planning on replacing the entire audio system in the S, I'm curious, however, if removing the stock HU of a '04/'05 S2000 also removes the stock remote entry function.

Any help or knowledge would be greatly appreciated.

 

You can replace the headunit and the remotes still work.