Maytag MMV4205 Microwave Oven - Answered Questions & Fixed issues

You will need to replace the 20 amp. ceramic fuse inside the unit. This is real easy and the fuse only cost around $10.00 You will find a break down of your unit at www.partselect.com just enter your model number and a break down will come up. Your part number is PS2052772. You can also locate where the part goes. Good luck.

Yes of course Google make model replacement parts

diode is connected from condenser to earth look to the right side bottom just under fan beware for a nasty shock

i personally do not recommend to a consumer to work on microwaves. they retain alot of voltage! but will refer you here.... http://www.appliancepartspros.com/repair-help/maytag-microwave-mmv4205aaw-repair/mmv4205aaw-wont-start.html

There are 2 fuses inside the cabinet. One is for the clock and turntable. The other is for the high voltage transformer and the microwave module. If this fuse is blown either the transformer is shorted or the module has failed to cause the fuse to blow. Parts and Labor can get close to the cost of a new one, so get an estimate so you can have information to make your decision

Typically there is a metal mounting plate screwed to the wall and when you take the screws out of the cabinet above it it will tilt forward toward you and then you have to lift it off of some metal tabs that are on the bottom of that mounting plate. Lift up and pull away from the wall and let the cord pull out of the hole in the bottom of the cabinet. Good luck. I usually do that by myself and hook one arm under it and lift it up, but probably better with two people.

Sounds like the on switch for the fan is fused in the on position. You may need to replace the switch

Use kitchen timer not cooking timer, it's written on your oven timer pad. I did that before

inside the case

Paul, if you look on top of the microwave before you install it you will see where the fan is located at the back edge. There should be 2-4 screws that hold it in place. Remove the screws and pull the fan up and out of the microwave and rotate the unit 90 degrees towards the front of the microwave and put it back in and replace the screws. That should be all that you have to do to get it to vent out the front.

The Magnetron Tube can be replaced but you should read the link before Consumer Complaints & Reviews

On a 1-10 scale- this is a 2. place a cardboard box on the stove to support the microwave once it is free. Remove power cord from the outlet in the cabinet over the microwave. In the cabinet over the microwave, locate the 2 mounting screws. Loosen each one about 6 turns- the microwave should drop down in the front by about 1/2 inch. Once loose, you can remove both screws completely and allow the front of the oven to rest on the cardboard box. While supporting the front of the microwave,have a helper remove the cardboard box. Tricky part...while supporting the front - angled slightly down, lift hard under the rear of the microwave and pull toward you. Have a helper feed the power cord through the upper cabinet bas as you bring the microwave toward you and slightly down. Place the microwave on the counter- with a towel in place to prevent scratching the counter. remove the rear-wall mounted support bracket. Done

You likely have a bad top or bottom door switch or its mount is loose, misaligned, or broken. See these help files: http://031d26d.namesecurehost.com/mwd/safety.txt http://031d26d.namesecurehost.com/mwd/disassembly.txt http://031d26d.namesecurehost.com/mwd/doorsw.txt You can order parts for most major brands from the Pros here.

You have a failing membrane keypad. With the full model number, I could have given you a detailed answer including part numbers, sources, and instructions. You can still get that at no charge by letting me know your full model number and symptoms, here.

If it went dead almost immediately after pressing the Start pad, that's usually a shorted high-voltage capacitor. See http://www.microtechfactoryservice.com/cap_test.html If it went dead several seconds after pressing the Start pad, that's usually a failing high-voltage transformer. See: http://www.microtechfactoryservice.com/xformer.html If it goes dead or blows the breaker (or GFI) when you plug it in or open or close the door, then there's a problem with a door switch or door switch mount. See our help file on door switches here.You can find helpful manuals, exploded views and parts lists here.Our favorite supplier is the Pros here.

It's probably the internal fuse.You will have to take the microwave down so you can remove the housing to get at the fuse.(I will probably install an accessable panel mounted fuse holder if this ever happens to mine-already did it on the little microwave I carry around on my work truck to heat up my lunch).

see this causes and fix it. God bless you Touchpad and Control Panel If the microwave buttons don't work the touchpad and control panel assembly are probably defective. Touchpad If the microwave buttons don't work the touchpad might be at fault. Generally speaking, if the display is working and some of the buttons respond correctly but some don't, the problem is with the touchpad. User Control and Display 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.

see this causes and fix it. God bless you Diode The high voltage diode converts the A/C power output of the transformer to D/C, doubling the voltage to nearly 5,000 volts. This high voltage powers the magnetron which emits the energy that cooks the food. If the diode burns out, a lower A/C voltage reaches the magnetron, which is not sufficient to power the magnetron. When the diode fails it is often visibly burned out. If it appears to be good, it can be tested with a volt-Ohm meter capable of testing diodes. High voltage diodes frequently fail and are one of the most common points of failure in a microwave oven. Door Switch If the microwave does not heat, one of the door switches might be defective. Microwave ovens normally have three door switches, if any of them fail the microwave does not turn on and does not heat. Check the switches for continuity with an Ohm meter. Magnetron If the microwave oven doesn't heat the magnetron tube might have burned out. The magnetron uses high voltage, high current DC power to generate the microwave frequency that cooks the food. If the microwave oven is turned on when it is empty this can cause the magnetron to burn out. Once it is burned out it has to be replaced, it's not repairable. High Voltage Capacitor If the microwave doesn't heat the high voltage capacitor might be defective. The high voltage capacitor works with the high voltage diode to convert the output of the transformer to DC voltage and to double the output voltage. If the capacitor is burned out the entire high voltage circuit stops working properly. The high voltage capacitor can be checked with a special VOM meter which has a capacitance testing capability. Be aware that the high voltage capacitor can retain a charge of more than 3,000 volts and can injure or kill a person if not handled properly. Only trained technicians should perform this type of testing. High Voltage Transformer If the microwave does not heat, the high voltage transformer might be burned out. Microwave ovens produce a very high voltage in order to power the magnetron antenna, which emits the energy that cooks the food. Thermal Fuse If the microwave doesn't heat the thermal fuse may have blown. It can be tested for continuity. Watch our fuse testing video for more information. Thermoprotector If the microwave doesn't heat the thermoprotector may have tripped. This is a safety device to prevent the microwave from overheating. It can be tested for continuity to see if it's blown. Main Control Board If the microwave doesn't heat the main control board may be defective. This is not common. When a microwave doesn't heat the problem is usually within the high voltage circuit; either the high voltage capacitor, diode, transformer or magnetron.

see this causes and fix it. God bless youLights come on, but can not program unit, Touchpad dead If you have a stuck key or non-responsive key, most of the time you will have to replace the keypad for this microwave oven repair. If your keypad is connected to your control board by a flat ribbon wire, try disconnecting it and clean the silver contacts with an ordinary pencil eraser. After cleaning, plug it back in and try it. If it doesn't fix it, replace the keypad unit. Some units actually have keypad tests to confirm your diagnosis of a bad key.If your keypad and control is the same unit, replace that unit. Another note, unlike stove/oven keypads and controls, most microwaves do not have error codes or tests to distinguish whether it is truely the keypad or control. Most of the time, it is the keypad that needs replacing, but a small percentage of the time it can be the control. Check the tech sheet if they can point you to the right part.

From the description it is the magnetron, it will be expensive for the part alone, and keep in mind shops have different rates making impossible to give exact quotes, but I would estimate parts and labour at least $250.00 or more, if you decide to go with the repair make sure the magnetron is not a aftermarket product it will last about 6 months.