I have a 54 plate Focus C-Max and the spare key has been lost. The original key i do have is a 3 button central locking key. Im going to get an extra key cut at some point.

ive got hold of a 3 button flip key thats the same as the key to my 2014 fiesta and was wondering if instead of getting an old style key, if i can get a blade cut on the flip key instead?

 

i’ve already programmed the central locking on the more modern key and it works fine but I didnt know if the transponder chip in the newer key would be compatible for cloning from the older style key?

One locksmith i’ve spoken to said it wont be and another said it would work fine. Anyone got any experience in such matters? 
 

cheers

You don’t need to pay someone to do the chip programming , it can be done with forscan on a windows laptop. Forscan for windows is free. You will need a obd port code reader thing eg from tunnel rat electronics for about twenty quid. These are handy for all kinds of fault finding so good to have anyway.  Transponder chips do vary by spec and shape. The one I got for a 2008 focus was 4d63 type and was lump a lump of carbon. Don’t know if yours would be same. I got key blade cut from a photo using someone on eBay. It all went to plan and I created a perfect 2nd key. Did this for my brother as a sort of challenge to see if I could.

I was just looking up 4d63 chips . What I found suggested cmax used 4d63 from 2003-2010 and fiesta used if from 2001-2016 . So perhaps you can use the fiesta chip.  But then something else I read said there are 40 bit versions and 80 bit versions of 4d63. So not sure.