Ah, I see where it is now, thanks for that mate. I was trying to get that pic and upload the pic on that like and upload it but Photobucket seems to be shagged tonight, but I know the bit you mean, it's basically on the lower left of the thermostat housing, no wonder I couldn't find it.
Thanks to all, hopefully it's either the sender or a wire off then but I'll let you know how I get on.

I'm pretty sure I know where I can get one of those.