Cant be, mine definitely had no chime and I've programmed my jag key myself. I do believe however, if theres no chime after turning ignition to position 2 4 times in 6 seconds to programme central locking that means that parts disabled using the keys.

I haven't programmed a key the old fashioned way myself for a while now but am sure it only chimes after you press and hold the button on the key you're programming

Trust me mate, I've done them loads of times. After turning the ignition off for the 4th time it should chime then it chimes again when you press a button.

Kl kl. Well if its not chiming for him then looks like its a trip to the dealers or sum1 with diagnostic equipment ;)

Hi Guys,

Just to update you - I changed the key fob for one with the exact same part code as I one I already had and working. This time the PATS programming stuck! I programmed it using the normal instructions and its starting the car all the time now. My problem must have been because the fob I tried first with a different part code was not compatible.

Thanks for all your advice has saved me a trip to the dealer which is always good!! :-)

I have just bought a second hand fob from ebay it doesn't have a new key blank as yet, its just the remote fob. I have sucessfully programmed the fob so that it can open and lock the doors remotely from the fob.

The problem I am having is I can't get the fob to start the engine with the existing key shaft from another key that is already paired.

I have followed the instructions of using two existing paired keys and putting them in one by one switching from 0 to II on the ignition to get me into the pats programming mode. As I am only holding the remote key fobs onto the key shaft it allows me to quickly swap the paired key fob over with the one I bought off ebay. I turn this from position 0 to II and remove the key.

Then I wait a while and try the new fob, it starts the engine, but it takes a few seconds longer than the working key would normally take to start the engine, but it does start the engine eventually.

The problem I am facing is that the key from eBay will only start the engine ONCE after I have run the pats programming procedure. After that it fails to start the engine anymore.

I then read about erasing all other keys apart from the original mercedes benz parts paired two, so I tried that hoping that the car already had known keys to it and it wasn't allowing the new key to be paired.

I ran the procedure in the book for erasing the other keys, then I re-ran the pats programming to pair the ebay key but I'm still having the same issue, the key will only ever start the car ONCE!

Any idea what I might be doing wrong or what could be the problem?

Your help would be very welcomed.

Thanks. (sorry for the long post!

I have this problem long time ago. I even ask my uncle about his programming skills but none of them helped me.