Diplomat grill and top oven not working?

I have a Diplomat electric double oven and grill - model no. ADP4520. The other day all the electrics went off (trip switch in the RDC) when I was using the grill. When I flicked the main switch back on I found out that the top grill and top oven was not working/heating any more. Bottom oven and fan work. Top fan works. Clock still works.
The top grill element looks easy enough to get out and replace but cant figure out where the top oven element is. My Diplomat handbook says that the grill element is 1800W and I can find a few of these on the net - but the top oven element is supposed to be 1600W; can't find any like this.
Also, It seems a bit weird/unlikely that they both go at the same time. Could it be the thermo? How would I test that. Also, could there be a safety cut off switch or fuse hidden inside that wants replacing. Any ideas would be a help to point me in the right directions.