It will be the circular element behind the back panel inside the oven that is at fault. Unplug from mains remove back panel remove element screws and GENTLY pull the element forward be careful the wires do not come off the element and make sure you know which wires go where, can be more than 2 wires, get it wrong and there's a big bang and the clock, stat, and switch can all blow! If worried about this remove oven first and remove rear of oven and take photo of wires .
Kenjo, March 2014