Temperature Gauge not working

[Big and Daft]

My Terrano (2000 TDi SWB) has been sat on the drive since September (lost my job, couldn't afford insurance, so SORN'd it)
I have re-insured it today and took it out for a 6/7 mile spin, after charging the battery it started fine, however, the temp. gauge didn't move at all.

The heater blew warm, about normal from what I remember and the engine ran fine with no noises. There was some smoke on hard acceleration, which cleared after a couple of seconds - but I only did that AFTER 5 miles, so the engine would of been warm. Dirty injectors from lack of use I'm guessing.


Any ideas? Temp. gauge was working before it had it's winter break.


Thanks!

 

[Big and Daft]

Also, while poking around under the bonnet looking for a 'press this to fix the temp. gauge' switch (didn't find it) I spotted this wire and connector coming from the alternator.
It looks like it should be plugged into something, can't see where - just curious as to what it's off?

 

[makeitfit]

Thermostat possibly needs changing

 

[Big and Daft]

Popped down to the shop today, about a mile or so and on the way home I noticed the gauge was working.

Must've not been used to moving after a 5 month rest.


Still not sure what that wire is for though