Hi, Thanks for your reply. I have read that by turning on the air conditioning that the fan should then always run? I have done this and the fan doesn't run. I have drove it for about 45 mins ....the coolant started boiling so i popped the bonnet with the engine running and the fan wasn't moving. I've done this 3 times. Can't understand why the temperature shows as normal when there's steam coming out of the coolant tank. When I start it from cold the temperature gauge starts low and then does increase though but never gets above normal even when it's bubbling??

No it doesn't work in getting cold but the fan should still turn if I turn it on?

On a trad system you can jumper the fan direct to the battery to check if its bust. If you connect it up the wrong way it'll run backwards, telling you you connected it up the wrong way.

You can probably do this even on an ECU controlled system, though I have no experience of them and don't much want any.

On a trad system, IF the fan works, check the fan relay. If its OK, check the thermostatic switch that controls the relay. Acdually checking it is a bit tricky, involving fiddling around with hot water and multimeters and probably burning yourself, but you can substitute a paper clip to short it out (since it makes a circuit when hot) and see if that makes the fan go.

If these are all OK, its the wiring between them.

But are you sure your car IS actually overheating? Has there been any work done that could have created air pockets, which can mimick overheating? This could explain why your temp gauge shows normal, or (since you have lost coolant) there may be an air pocket next to the sensor.

Or its bust

I thought all thermostats of this year were failsafe? {fail open) ?

What year?

But whatever year, they are a pretty simple mechanical device (unless they've been "improved"?). Hard to see how they could be guaranteed to jam open, rather than jam closed.

In any case, I'd say (a) first thing to check would be whether the fan is bust, which even on a modern car should be possible by simply hooking it up directly to electricity

And (b) ,since the OP hasn't shown any interest for a while, it probably no longer matters.