Hi ,I have just had a similar problem on my diplomat grill/oven, although I think I have a different model.I had to take the oven out of the housing and remove the cover going over the top and down the back. I then traced the wires coming from the front button to where they met with wires coming from the bottom. Where the connection was ,there was a little red button that I pressed down. Make sure that you diconnect or isolate from power source !!!! I hope that this may help ??
Davie, July 2008