Temperature guage sensor goes zero when driving

i own a 2003 peugeot 406 EW10 engine in petrol and my problem is then when im driving usually over long distances the temperature gauge shuts dwn momentarily and goes to zero, the display then gives a warning "ENGINE COOLANT TEMPERATURE TO HIGH" and STOP STOP STOP comes on. after a short moment,it roars back to life but when it doesnt i stop and switch engine of then a wait a couple of minutes then restart and everything will be normal. i hav taken the car for diagnosis and it reads COOLANT - INTERMITTENT THERMISTOR COHERENCE. the fault is cleared but returns. i ahv also changed the temperature guage sensor but to no avail. any1 ever experienced such a problem

 

Mine is a 2002 diesel 406 and has a similar fault.
Temp gauge will drop to zero, but none of the warning lights come on.
Drives ok, returns to normal after a few minutes.

I mentioned this to the dealer who indicated it was a common fault and was fixed with a modification of some sort to the sensor or the coolant reservoir.

Going to the dealer on 29-Jul-2015 so will try to remember to report back.

 

Had similar problem. 406 2004.Cleaned the three radiator fan relays and connectors inside the box on the left of the single fan and the radiator sensor connector. Located on the bottom right.She responded well.