Key that used to work fine is now "Not Recognized"
is there something I can do it is this a dealer only thing?

Thankfully the second key works fine

 

Mine does this occasionally, usually when it is in close proximity to my phone. Is it doing it all the time? Did you try a new battery?

 

Yep, new battery in. Phone nowhere close

 

Mine did that too and a new battery did not change it. I suspect that perhaps the contacts for the battery may need to be cleaned. Someone also thought the fobs just wear out over time. I have a second one that was never used and the message came on to change the battery which I did and it works fine.

 

Happens to me every once in a while. I found that if I lock and unlock the car, using the key fob, it works. This while in the car.
hope it helps in your case.
Tony

 

When mine completely failed and my cell phone was locked in the car I tried it a few times then shook it a bit and it worked, that's why I think the contacts for the battery might have been dirty. When I changed the battery I noticed the battery that was in the fob was the same brand as I was putting in, I think maybe the dealer or independent may have changed the battery without telling me. I should go back in and clean the contacts. It is nice to have a new non scratched up fob though. I checked the voltage on the battery that was in the fob that didn't work it it showed 3 v, while the one that gave me the message on the dash to change the battery was only 2.7v and it still worked but I put in a new one anyway.

 

"Key not recognized" + KESSY problems - Rennlist - Porsche Discussion Forums