Whirlpool mwn 410s

Get the door safety interlock switches tested for continuity and alignment, by a qualified service engineer.
If a door switch is not switchimg. there will be no power to the magnetron and no heating.

it contains two fuses one of 10 Amps and other for 500mA.
Replace 10Amps fuse with same type and rating.Best thing is to take this fuse and show it to the sale person of electronic shop.
Before you touch any parts of the microwave oven please disconnect the mains power chord and never touch the main power capacitor as this contains very high voltage even after disconnection.

see the details and proceed according. fix it. God bless you
Main Control Board If the microwave buttons don't work the main control board is most likely defective and will need to be replaced.

Main Control Board If the microwave buttons don't work the main control board is most likely defective and will need to be replaced.

Main Control Board If the microwave buttons don't work the main control board is most likely defective and will need to be replaced.

Touchpad and Control Panel If the microwave buttons don't work the touchpad and control panel assembly are probably defective.

follow the next step, use the common sense, God bless you

1. No power to outlet (overload or fault in microwave or other appliance).
2. Blown main fuse - likely due to other problems.
3. Open thermal protector or thermal fuse.
4. Defective controller or its power supply.
5. Clock needs to be set before other functions will operate (some models).
Tight any connector. see the picture.

The problem is in the magnetron or the inverter board.

Assuming your power line voltage is okay, it would not surprise me that after 27 years, your high voltage capacitor is drying out and increasing its capacitance. This will cause variance in the high voltage output, which can stress the magnetron and increase current consumption.

You can order Whirlpool parts my model number here.
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For more free DIY and other help & advice, feel free to contact me via my site.

William E. Miller, AS-EET
http://www.microwavecontrol.com
Microwave Oven Control Panel Repair Nationwide
"Recycling by repairing since 1982"

there is very high voltage present even when disconnected from mains. unplug from mains & leave for 1 hour. remove cabinet. there is a fuse which controls everything usually located near the transformer or where the mains cable enters. check fuse and replace. it needs to be the correct fuse for the appliance
There should also be a "mini-manual" (tech sheet) hidden inside the unit behind the control panel or hidden on the left side behind the grille, which is very helpful when troubleshooting, testing, and locating components.

Once you remove the control panel assembly, the fuse is located in a holder behind that area toward the top. The tech sheet shows part locations

yup most probably that is the case.

you can locate the fuse usually it is placed near the main power supply or just trace the supply cord going in your unit. but before you open your unit be sure it is unplug to avoid electric shock.

slowly disassemble the unit and be sure that you can replace all the screws back to it original positions. after locating the fuse, check if it has a continuity and be sure to replace the same fuse rating. also investigate why the fuse had blown up and look for abnormalities.

if nothing found then replace the fuse and put all back then test the unit. if still it blows fuse, their must be something wrong with the unit and have it service to qualified personnel.

Check your main breaker fuse in your panel/subpanel.

Otherwise if the inline fuse is good and the main power is good, then look at the power supply for the microwave.

Mike

be very careful cos microwaves can kill - there is very high voltage present even when disconnected from mains. unplug from mains & leave for 1 hour. remove cabinet. there is a fuse which controls everything usually located near the transformer or where the mains cable enters. check fuse and replace. it needs to be the correct fuse for the appliance