MT4155SPB - Instructions

After determined the problem on one of the websites...I received the part I needed... removed the control panel and installed the new main fuse In about 15 mins!

-Removed cover ("Star-pin" head security bit needed for this)
- Removed leads from hi-voltage capacitor
- Shorted cap leads with insulated wire to make sure it was dis-charged.
- Removed cap and the the hi-voltage diod
- Installed new parts.

Unfortunatly, still no mwaves (heat) produced, so this means it is the magantron that is dead. Will replace that next.

The hardest part was taking it down from the range hood stand. Without being able to open the door, the glass carousel was moving around. We removed about 7 screws. Luckily we had the special type of allen wrenches (ones with a hole in the middle). It was easy to see what had broke and that it would not be fixable. We tied fishing line to the door hooks so that we could use the oven until the part came in. When I seached the internet and logged onto your site, keyed in the model # and the item I needed was the first item with a picture. I was absolutely sure it was the right part. The price seemed high, but I checked with our local applicance where I bought the oven and it would be the same cost from them and they have always be reasonable. Ordered the part, arrived within 2-3 days and it took only 30 minutes to install. You need to press down on the side of the part (spring loaded) to pop it in place. Helpful to turn the oven on its side to get leverage. Just go slow as the part is plastic. I will use your site again. Thanks.

I removed the unit from the wall. Took the cover off. Set the unit on its side. It revealed the working parts. Removed the old micro switches. Put in the new oness. Presto, it worked. Very easy for me.
The parts was delivered almost before my notice they were shipped.

I tried to fix the wheel but the plastic hub had worn too small. After messing with it for a month, I ordered the support ring with 3 wheels from this site. this site said it would fit many brands of microwaves. I was glad I ordered it. It was very affordable and is better than the original. The replacement part is made with heavier duty material than the original and it works perfect. I picked up the microwave plate and grabbed the old one and threw it in the recycle bin and put the new turntable support under the plate, put the plate back on top and closed the door!! Works perfect! Even a novice can do this repair!!

1. Removed cabinet screws (10-15?). 2. Removed cabinet. 3. Removed top interlock switch which actually was not defective. The press clip connection appeared as if it had been arcing for quite some time and the corrosion created resistance sufficient to prevent the current from getting through the switch. 4. Replaced switch anyway but broke plastic retaining clip despite every effort not to do so. Reset broken clip with super glue. 5. Reassembled cabinet and appliance is in good working condition.

Problem would come and go. Found service schematic inside unit. Perform all the suggested tests. One possible solution was the primary interlock switch shown on the schematic and a check found the switch stuck. It would free up some times but would stick again in the open position. Ordered switch which was a simple plug in unit.

new glass tray

Make sure to have your model number correct. First tray I purchased I didn't use the model number and just picked what I thought would work (KitchenAid), but didn't. Second attempt I put in the model number and received the correct one. Take out of the box and into the oven, that easy.

Fun and easy fix for my kids.

The countdown timer was working but no "cooking" happening. Did not hear the familiar sound of the heating part working.

Determined it might be some simple switches for under $15 dollars. Bought one of each. They allow the microwave to turn on/activate by signaling that the door is properly latched. My wife noticed that it was failing and then failed over the course of about a day. Several times where it worked, then did not work. The timer was counting down one time and then when she opened the door the microwave heating component turned on. Guess it had activated the switch as she was opening the door.

Procedure to repair
- Unplug
- Remove two screws on front top - allows you to remove the vent. Realized there was a charcoal filter there that I had never replaced so ordered that after the fix.
- Remove two screws to pull off the front right panel (area where your microwave buttons are) One at the top under the before mentioned vent and one under the microwave on the far right corner.
- Have someone hold the panel because wiring is to short to place it on a ledge while connected or take a picture and remove connections. I simply held it while my daughter undid the micro switches.
- Carefully remove micro switches. There were two "orange" button ones so I chose the top one to replace along with the green button one that I had ordered, so I simply pulled an orange from the bottom and a green from the top latch area. You may have remove the part that holds the switches since it was a little tough with the wires in the way and not knowing how the switches stay put.
- plug in new switches and place in the brackets that hold them in place
- reverse everything you did.
Viola - a working microwave vs purchasing a brand new for several hundred dollars or having to call in a technician.I love that my young kids did this project with me and we actually got it running. Don't like to have to throw away more items at the landfill.

Semi-Handy Man

I removed screws from the cover, then I removed the screws holding on the front panel. I then unplugged the connectors, and removed the front panel and broken door latch. Then all I needed to do was slide the new door latch in the spot where the broken one was and put it back together. The only thing to note is which way the yellow and white and the blue and white connectors are on the front plate (location and wire direction). All is working well, and I can open the door again. Needless to say I feel better about repairing the microwave rather then throwing it out getting another one and creating more electronic garbage in a landfill .

I had to remove the housing cover that had about 8 tamper proof screws in order to remove the cover and get into the area where the brkt-latch was. I removed the broken latch found the part I needed on your website, within a few days the part arrived. It took only a few minutes to reinstall the new part and housing cover. Everything works just fine. My guess is we saved $200 from having our local repair service center to do the same job.

I decided the door switch was the problem because 2 problems happened at the same time. I removed the 4 screws for the top outside cover and the 1 screw that held the control board. After removing the control board screw, I lifted it up and removed it. This gave me access to the 3 door switches. I then removed the 2 screws that held the plastic piece that holds the switches. This made it easier then to replace the switches.

tested all 3 of the door switche for continuity, the top switch was faulty, replaced it,for approx $4.00 and saved a $350 dollar microwave.

Over the stove microwave installed in top cabinet row.
1. Unplug device.
2. Two people to remove from wall/cabinet (remove two, large, top mounting screws and rotate entire microwave down and off the wall mount). Should be some wood spacers between top of device and bottom of cabinet.
3. Remove screws from sheet metal cover.
4. Remove one screw holding blowers in place and rotate out of the way, in order to gain access to 2 of 5 screws that hold the magnetron in place.
5. Unplug magnetron and remove the 5 screws.
6. Drop in new magnetron and re-assemble microwave in reverse order (steps 5-3).
7. Two people restore micro to wall/cabinet. Replace wood spacers, re-install two, large mounting screws (finger-tight). Test device. Secure the two large screws.