Didnt have hole in the wall for the fan to release the air. ran fan and everything went out.

The microwave is not supposed to shut off if you have food in it. it is designed to stay running so you will not forget your popcorn.

Sounds like the main fuse blew. It's either near where the power cord enters the cabinet, or behind the control panel (if an over the range unit).

You may also have some type of failure in the high voltage circuit; based on your description of the symptoms.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/david_29ad5d1dd86564b0

follow this steps and fix it. God bless you

Waveguide Cover

If the microwave is sparking or arcing the waveguide cover might be damaged and shorting out. Try removing the waveguide cover and see if the problem goes away. If there are any damaged spots in the microwave ceiling or sidewalls, repair them and paint them with microwave oven paint. Replace the waveguide cover if it is burnt or if it will not stay in place.

Microwave Oven Paint

If the microwave is sparking or arcing on the side walls the paint might have chipped causing pitting in the metal oven wall. Use microwave safe paint to touch up any bare metal spots.

Rack Support

If the microwave is sparking or arcing near one of the rack supports, remove the support, repaint any bare metal, install a new support.

some fans have a charcoal filter that needs replacing others are supposed to be vented out side by the roof or out the wall to see if the vent is going outside you will have to unmount the unit tak it down and check and see if it is conected to a duct in the celing or through the wall hope this helps

I would think the main fuse may have gotten hot due to a bad fuse holder. If the fuse holder gets old and doesn't grab the fuse tightly it is an opposition to current flow, which is a resistance, and any resistance will produce heat, heat will make a fuse melt in its end and go bad. So, either that or something else just shorted out and blew the fuse inside. Need to call a technician. But the fact it finished its cycle then was dead when you went back makes me think the overheated fuse thing.

We have the service manual and have uploaded it to our site here to help you.

From page 33:

OVEN LAMP and Lamp Socket REMOVAL

1. Disconnect the power supply cord, remove the oven from
the wall and remove the outer case. (Refer to procedure
of "Removal of Oven from Wall" and "Outer
Case removal ".). And proceed as follows.
2. Open the door and block it open.
3. To discharge the high voltage capacitor, wait for 60
seconds.
4. Remove the three (3) screws holding the hood intake duct
R to the oven cavity top plate, the oven cavity front flange
and the fan duct. And remove the hood intake duct R.
5. Turn the lamp socket and release it from the magnetron
duct.
6. Screw the oven lamp off from the lamp socket.
7. Now, the oven lamp is free.
8. Pull the wire leads from the oven lamp socket by pushing
the terminal hole of the oven lamp socket with the small
flat type screw driver.
9. Now, the oven lamp socket is free.

You can find helpful exploded view diagrams and order parts by entering your full model number here.

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There is a varistor or thermostat switch mounted on the wall behind the control panel. I unpluged the leads and shorted them together. the fan and lights started working again. I got another microwave off freecycle.org for parts. I noticed a lot of sites tend to point to the control panel for a $36 to $100 board repair. Don't fall for it. H.G.

The issue is that the fan on that unit is a reconfigurable fan. If there is a vent, you install the fan one way, if there is no vent pipe to the outside, you install the fan another way. https://www.manualslib.com/manual/294916/Maytag-Mmv4205.html?page=9#manual

Hello staufferbi,
It is possible to redirect the vent to the outsied but it is not a simple task. First off, you will need to remove the micro from the wall cavity and reposition the blower so that it vents out the top and not the front, then cut a hole in the cabinet above the micro ( lined up to accept the rectangular duct ) These tasks require fairly good carpenmtry skills and may not be suitable for the novice.. In any event, if you do attempt this.. then once you have the duct vented through the cabinet from the top of the microm you will need to attach that to wall vent feedthru. This normally means converting the rectangular duct to 4inch round and using an elbow. Needless to say, it can be done but is fairly involved. I did not mention anything about getting a 4 inch hole thru the outside wall and not thru a wall stud.,. Outside walls are typically bearing walls and although your roof won't cave in if you cut a hole thru a stud, it isn't advisable. Then you have to make sure it is sealed thru the wall cavity and properly cut into your siding. As I said before..it can be done but don't think it is a little job..
Good luck
Rick

Yes, the mouse was probably attracted to the warmth and food odors in the duct work and may have gotten trapped in the vanes of the fan and died. I'd act fast...

The best bet is to remove the oven from the wall, or almost from the wall, so you can see the area of the hood vent exhaust fan.

This is safer with two people and the installation instructions will be of great help.

You can download GE owner's manuals and installation instructions here.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.