So it can sense the temperature of the water in the engine,gives a more accurate response.

As for wiring,it's honestly idiot proof,it should only plug one to one.failing that,get into your service department asap and grab the autodata wiring diagram,don't panic if it's uk only,very similar under the bonnet so you can at least identify exactly what all the wiring is.

Most jap cars are very user friendly,yes it's tight in there,but they love to use nice colourful wiring like a red and green together (no use if your colourblind i suppose!!) rather than fords genius idea of black,black with an almost black blue line and black with an almost black purple line through them,dead helpful!!!

I know you think I talk shit sometimes but it would honestly have been easier as a home mechanic to have dropped the engine and subframe out in one then worked on it,there's only 3 plugs (iirc) then to reconnect and a few pipes,which again are obvious,still,it's done now.