shit sorry forgot to say its on my 2wd saff not the fiesta.. well the fan switch is brand new ford one.. the original wireing for the fan gave up when had the old engine in so i re wired it to the battery with an inline fuse .. seemed easier at the time rather than tracing the original wires back to find the fault.. also tried to buy one of the replacement fan looms from abc motorsport but they have none letft.. thought this adjustable sensor was an easier way of sorting now as would be independant.. was originally worried that the engine was not cooling properly as the fans stayed on even when driving but has been to 2 well known garages 1 was for the setup and told its not running hot.. i wondered if wher i wired directly to the battery had too much current running through the ford fan switch and while the car running fused the switch terminals .. once engine off less current and switch frees.. i just ran out of ideas.. even tho the temp gauge reads just below the O on the norm the engine , rad and hoses never feel that hot.. just thinking of the traffic in the summer really and i may forget my switch..