I know a few people want a guide on how to do this so here goes
You will need a laptop running windows and a copy of the programme called Forscan With an Extended Licence
You also need a compatible cable like this one
https://www.ebay.co.uk/itm/New-Modified-ELM327-USB-Ford-Elmconfig-Focccus-Forscan-Focus-Smax-Mondeo-Kuga/223210794515?hash=item33f8666e13:g:CXYAAOSwlY5bv393:rk:2:pf:0
You need to connect your car to forscan using the cable and select the following menu
Make sure your cars battery is fully charged as this can cause issues with the program once the screen prompts you to open the SBL it should give you the option to make a back up i suggest you do in case anything goes wrong when loading
Once you hit continue forscan will load all the modules in wait until this has finished this should take 60 seconds IGNORE ALL THE LIGHTS AND CHIMNES COMING FROM THE DASHBOARD this is normal follow the messages on screen if it prompts you to switch the ignition off do so you will then be greeted with this menu
From the drop down menu at the top left you may need to select engineering mode 2 for the keyless menu to appear
On the column above look where it says (without keyless entry and start) your RS should say WITH KEYLESS ENTRY AND START double click and a menu should appear you need to select with KEYLESS START make sure you select the correct one
Once you have done this Hit the WRITE Button at the bottom on the screen forscan will load all the modules again it may as you to cycle the ignition off
Because all the modules are loaded this can cause some hidden dtc to be stored You can clear them using forscan
I would suggest you only attempt this is you are familiar with forscan
Hopefully this helps a few people and protects there RS