I bought a new key fob (case only) and sat down to swap the internals from my old key. I did the metal key putting that in the new case but couldn't get the bottom apart so decided to plug that into the top bit.
I opened the car ok with the remote. I tried to start the car but it turns over a few times then stops. It displays 'SAFE' on the dash lights. I now know that the top part of the key has some electronics in it and have now put the old key back together. However it still says 'SAFE' and I can't start the car. I disconnected the battery to try to clear the problem without success. And now the remote locking of the key fails too. Next stop Audi and a fat bill ?