hi all . i am looking for some advice regarding my key . last week for no apparent reason my key fob stopped working it just refused to operate the central locking . so i got myself another key off ebay its from the same car as mine with the correct part number now bareing in mind i only have one key can anyone shed any light on how to program it to my car which is an a4 1.9tdi 2004 reg.i have swopped the transponder from my original key so i am able to unlock the drivers door manually and start the car . so its only the central locking part that i need to program any help would be very much appreciated