When I got this car it only had one central locking remote so I ordered another one.

Following instructions I turned the car on and off 4 times until I got the beep and then pressed a button on the remotes to program them back in and they both worked.

Recently the remote I got with the car quit working as well so I replaced that one and now no matter how many times I turn the car on and off it simply will not go into programming mode to allow me to add the new remote.

I did switch the transponder from the old remote into the new one and the key starts the car fine but I just can't get it to go into programming mode.

Any ideas?

One thought,only 4 unique key codes with remote can be programmed in.Maybe you are at your limit?Do you know the  key history of your car?One further thought,up to 8 keys can be programmed if you don’t add the remote.I think all this correct but not 100% because I haven’t added keys myself on the MK1.Hope this helps👍

I would not have thought that would have prevented it from entering programming mode though because there would have to be a way to overwrite old keys.

---edit---

I just found this referring to remote programming on the focus:

"Entering the programming mode erases the Focus computer's memory of all previous authorizations. Therefore, you must program all remotes that you want to work all in the same session, even if some are already working."

Ok so I take from that,after clearing the memory I think 4 unique key codes with remote can be programmed into ecu.I know this doesn’t help you but just saying.