Smeg oven not heating, any advice?

[orteil]

Hi there,

There's something wrong with our Smeg oven, and I can't figure out how to fix it.
The oven model is SCB91MF (double fan).

The symptoms are that no matter the program used, nothing heats up. That is, the two back fan elements, top and bottom elements, top grill, none heat up. However the inside lights, thermostat light, timer etc... work fine. I also noted that the left fan does not turn on and has more friction than the other (working) one when turned by hand. The oven never triggered the circuit breaker.

I of course made sure the oven timer was in manual mode.
I tested the thermostat with a lighter near the sensor and it senses correctly the increase in temperature, so that looks good.
I tried to reset the oven by shutting down the power for half an hour, no effect.
I looked at the two circular elements behind the back plate, they look fine and a continuity test proves no fault.
I also short-circuited the timer relay, no effect. (now that I'm writing that, I notice that I did not try to test it in open circuit... worth the test?)

Is there some kind of internal circuit breaker that would cause ALL the elements to stop working? How can I test the fan motor to see if it is really broken?

Thanks a lot in advance for your help!