MMV4205AAS - Instructions

Unplugged the microwave. I opened the door. I used a butter knife to pop the bezel off the inside of the door. I pushed the locker up and to the left and used the butter knife to pry it loose. Disconnected the locker from the spring, and reversed for the installation.

Repair was very simple, removed microwave from wall and removed top cover and found fan loose on shaft. Removed fan and motor, new motor and fan slotted, good upgrade. Installed new motor and fan and top cover on, installed back on wall plate, tried and wife said it sounds like a new one.

Watched a you tube video prior to installing new switch. Followed the video which gave me confidence i was up to the task. After removing the touch pad I found my design was not exactly like the you tube model but I found the defective switch, replaced it and put the microwave back together. Works great. Again watch the videos

You Tube

Replace (after testing w/ohm meter) diode and locker holder. My door often would not close properly. Microwave let know by saying not shut properly. When disassembled found the top screw mount was hollowed out resulting in it moving on occasion when you close door. First remove casing (special safety torx head) needed for rear screws. Onc e removed all parts available to view or work on. Diode is on the capacitor so caution is needed when removing. Serious shock hazard if touched. Use insulated pliers to remove from capacitor and a phillips on the ground. Test with ohm meter Should have resistance on way and non the opposite. Replaced mine bad. Next the holder 2 phillips screws and its yours. Unplug each switch and remove. Take note to what wires go to what switch and what switch mounts where. Mine had 3 switches. Removed from old holder and put in new. Screwed holder back in place and left scrws loose till re wired. Once wired set the holder by lightly tighting the screws. Try the door till it seats properly ensuring that all 3 switches are working properly. If so thighten screws. If all seems to work as advertised, safely plug in and test unit if heats up un plug and put cover back on micro. Your all set. Happy heating.

I had a son put in the new light bulbs. Rather simple

tested cap. with ohm meter which showed a short. A new HV cap., a fuse and it is working fine again.

It was not the magnitude of the repair but the fact I ordered the part on a thursday and it was delivered on saturday. Timing ws very important, especially this time of year.

using the measurements shown in parts catalog, it appeared the item I needed was correct for what I ordered.

Philips screwdriver
Removed screw (1)
Removed light bulb
Put in new light bulb
Closed door to bulb compartment
Returned screw.

Pro tip! Check how many bulbs you need before ordering. Mine only needed two. I got two. I suspect I’ll buy a new microwave before new bulb burns out again. Ordering/delivery was fast. No need to have spare on hand.

replaced plate

remove the part from the box and wipe it down with warm soapy water, rinse and dry and place in microwave.

I UNPLUGGED the microwave and removed the cover, using a phillips and a Torx screwdriver for the machine screws. I set these screws aside, so as not to confuse them with the later encountered screws. I photographed the magnetron to assure proper placement of the 6 phillips machine screws involved in reassembly (marking the the locations on the old magnetron would do as well. I marked the old magnetron "old", to avoid later confusion. I removed the two screws holding the shields to the magnetron. I removed 3 of the 4 screws holding the magnetron to the microwave, leaving one of the top screws. I held the magnetron securely and removed the last screw, pulling out a the part of the magnetron that penetrated the microwave. I installed the new magnetron in reverse order. One problem I encountered was locating one of the six screws, which had been pulled into the old magnetron by magnetism.

Removed door from microwave and then popped the inside widow trim ring off. Removed 4 screws from the window bracket, replaced the latch with a new part and then assembled.

Initial failure of over range microwave Aug 3rd. Control Panel worked but no heat. Took to local LG authoriaed local repair place. They fixed it quickly and we re-installed it. Worked fine for 2 months then had similar failure again. Agaim took to same authorized repairer. They kept unit for 3 months but finally concluded theu could not fix it and suggested we contact LG for a partial refund. When they tested the unit during re-assembly in my presence, there was a blue flash and the fuse blew. Since we had built a custom tile mural back splash around this unit, I brought it home, ordered a number of time delay fuses new capacitor and two new high voltage diodes. However, using my Fluke DMM, I checked the existing capacitor and high voltage diode and they checked OK so I just replaced the time delay fuse. The high voltage transformer leads had 2 possible ways to connect to capacitor and diode. Tried one way, plugged unit in and turned it on, and immediatly blew the fuse. Replaced the fuse and reversed the high voltage transformer connections,amd turned unit pn, and it worked perfectly. Since we had experienced several power failures during the time of the original failure, the repairer concluded that power spikes might be at fault, so I also purchased a TrippLite ISOBAR4ULTRA 3300 Joule surge protector between wall outlet and microwave, and re-installed over range. It has worked perfectly since.