The self clean cycles often go way above 500F.
This produces lots of smoke, so open your windows.
It turns the food to ash (which you then sweep out). Problem is many things are made using electronics today.
Often high heat for such a prolonged time takes out the electronics.
Most common complaint I hear with ovens is “I was using self clean when…” you fill in the blank, door wont open/close, display dead, error messages and beeping.
Good old baking soda and small amounts of water is best (once an oven is cleaned manually it does not self clean as well as before).
I use my household steam cleaner to clean my oven. It best to prevent spills in the first place.