Since you posted this under the WMH32517AT
category, I'll assume that's your model number. If not, feel free to e-mail me (below).
The function of the door switches is to prevent the oven from running when the door is open.
If the switches fail in a certain way, it can cause the fuse or breaker to blow. That's by design.
Some models have a line fuse and another fuse for the controller low voltage transformer.
There is a technical sheet hidden behind the grille or behind the controls. It's very helpful in locating components and testing, etc.
Your door switch mounts need to be inspected to be sure they're not loose, misaligned, or damaged. If so, they'll need to be realigned or replaced as needed.
The hook-like "latch heads" protruding from the door must be under spring tension and must move up and down freely in order to activate the door switches.
It sounds like your door switch is stuck, and you can order a universal type here
Most door switch problems
are caused by slamming the door or opening the door while it's cooking instead of hitting the "Stop" pad first.
At my Web site
, I have a video available showing how to remove a typical over the range grille and control panel assembly in under 5 minutes.
The support page for model WMH32517AT
. It has the owner's manual, installation instructions, exploded views, and parts lists.
You can order any needed Whirlpool parts from the Pros here
, my favorite affiliated supplier.
For more free DIY and other help & advice, feel free to contact me via my site.
Please include FULL model number*, FCC ID number*, + detailed symptom information. ( * on the tag in cooking cavity or around door frame or control frame or on back)
William E. Miller, AS-EET
Microwave Oven Control Panel Repair Nationwide
"Recycling by repairing since 1982"