Mine has done exactly the same!
At the back is a raised silverish panel held on with 7? screws.
Behind this is the heating element along with 2 thermostats, one for low and one for high temperature. Check these and the elements for continuity (you need a meter) . On mine one of the thermostats is open circuit, now all I need to do is find a new one!!
Good luck
Nigel
March 2006