When you set this oven to the desired temperature, it turns on normally and begins to heat up. At a random time in the process to keep the oven at that desired temperature it turns on the broiler element (top one) and it never goes off. If left unattended in this state it eventually locks the door (thinking it is in cleaning cycle) and you have to switch off the breaker and let it cool down.
Thinking it was the oven temperature sensor, I replaced it…but alas, it is still occurring. 
Any ideas to help pinpoint the problem and get the right part?
Thanks!