Hi,

Maybe check the thermal fuse.
You can see the thermal fuse linked here.

A copy:

Symptoms of a blown oven thermal fuse include:

The upper oven failing to heat or losing total heating function
Burning smells emanating from the upper oven cavity
Safety shutdown errors related to over-temperature conditions

Common causes are airflow restriction trapping heat or faulty wiring allowing overheating. Natural aging also deteriorates fuses over extended use cycles.

I hope this helps,

jeff sr.