could be a number of things,
more than likely the sensor, the wiring or the gauge itself, i'd take it to a garage then you can blame them if it goes wrong :P
The temperature gauge sensor on the 2002 F150 is located on the driver's side of the vehicle and under the intake. This is almost impossible to remove without removing the intake itself.
they are 2 totally different mdels. Vectra B is from 1995 till 2002, and was upgraded in 1999. Vectra C/Signum is the latest model from 2002 till 2008, and then you of course the newest Vectra D introduced early tis year.
I've been told that the outside temperature sensor is located under the front bumper.
In the transmission.
The ecu unit in a 2002 Vauxhall Vectra is located in the engine compartment of the vehicle. The computer can be seen behind the engine in front of the firewall on the passenger side.
On a 2002 Ford Ranger : The check " gage " light comes on if : The engine coolant temperature is TOO HIGH The engine oil pressure is TOO LOW or The fuel gauge is at or near empty
1800 cc's.
The water temperature sensor on a 2002 Kia Sedona is located on top of the engine, near the upper radiator hose. It relays the temperature to the vehicle's computer and triggers the cooling fan to come on.
there are three on my vectra c 2002 1 is in the engine bay on the left and 1 in the passenger side of the dashboard and one in the boot
Temperature Gauge Sending Unit The sending unit is located in the front section of the intake manifold in the vicinity of the thermostat.
On a 2002 Mercury Mountaineer : The " check gage " light comes on if the engine coolant temperature is too high , the engine oil pressure is too low , or the gas gauge is at or near empty
Either an air lock or a faulty switch at the stat. If its not using water i would replace the sender (switch). Hope this helps.