My Ford Fiesta TDCi 2013 has a fault with the heated windscreens. One day they will work the next they will not, it happens to both at the same time. It has been in to Ford for repair but to no avail was the same when I got home, all the electrics have been checked thoroughly, the sensors and relay and they work fine for a while but then don't. The next day they are fine for 2 - 3 days but then stop working again once again after 2-3 days are fine, cost me £90.00 at ford for nothing, has anyone any ideas please ?