HELP my vauxhall corsa temperature guage is always in hot position how can i make it work again?

I have a Vauxhall Corsa 1.4 Sport and my temperature gauge is always in the hot position what could cause, many thanks|||well that is a short in the system.the temperature gauge will have a sender unit on the cylinder head to sense the temperature and via a wire it sends the signal to your gauge.you have to find the temperature sender unit on the cylinder head,then disconnect the wire from the sender unit and with the ignition on but not the engine running check to see if your gauge has dropped to cold. if it has dropped to cold that would meen that the problem is in the sender unit.if the gauge hasnt dropped to cold,then you need to check and trace back the temperature wire to the gauge for a short.look for any part of that wire that mite be split and touching the body of the car.then if all those areas are clear with no problems your going to have to remove the gauge and get it repaired or replaced.i hope this helps to solve your problem from a mechanic for 23 years.