LD10 - Instructions

I had to unmount the over-the-range microwave oven to be able to gain access to the interior of the oven. Complicating removal (and re-installation) was the fact that there is a "pot-filler" faucet installed directly underneath the oven. In retrospect, I should've removed the faucet before doing the repair, but "c'est la vie."

After I got the microwave down, removing the case was also "interesting." I get bonus points for the fact that the previous owner must've had to replace the same diode before - and then re-assembled the microwave case incorrectly - thereby adding to the confusion (BTW, the service manual that I found online said nothing about how to remove the oven's case).

To remove the case, undo all the screws holding it on, and then rotate the case upwards from the back while also pulling the case backwards. There are crimped folds on the inside of the case that mate with the back edges of the front of the oven's chassis, and these folds have to be unclipped from the chassis in order to remove the case.

Replacing the diode itself was the easiest part of the job. The two connectors on the diode are of different types, making it impossible to install the diode with the wrong polarity.

BTW, the diode that had failed was not an OEM diode; I suspect it was a generic component that had been installed by a repairman sometime between 2004-2008 (when our home's original owners still owned the home). On the other hand, the new diode from PartSelect is an OEM part (it came packaged in a sealed Whirlpool bag).

The fact that the oven had stopped heating indicated that it was either the high-voltage diode or the magnetron that had failed. Since a replacement diode costs ~ 1/10th as much as a replacement magnetron, I figured it made sense to replace the cheaper part first. Fortunately, this fixed the problem.

One last thing: I tried testing both the old and new diodes for conductivity and polarity using my volt-ohm meter (VOM), but I was unable to get either diode to "turn on," even though my VOM is powered by a 9-v battery, and I used the 2-Mohm range setting. I guess the test voltage of my el-cheapo VOM isn't high enough to exceed the diode's threshold voltage, (even though I have successfully used this same VOM to test low-voltage diodes).

The power on the microwave went completely out when I went to use it, but there was no power failure for the house or neighborhood. We removed the microwave from above the oven. Took out the screws on the sides and back of the microwave and slid the top back. The line fuse was located on top unobstructed, NOT behind the button panel like some microwave models. As the appliance is over 20 years old the line fuse was quite old. It was really hard to pry it out of its holder and actually broke. I used a vacuum to suck up the dust and glass and it was easier to get out the ends once the middle broke. Popped the new line fuse in, slid the top back on, put in the screws and put the microwave back in its compartment above the stove. Good as new!! We were about to spend money on a new microwave, but thankfully I came across this site. So happy I did!!

This repair was really easy. The part that took the most time was taking it down from it's compartment above the oven and putting it back up there once repaired.

Access is via RT. SIDE Panel as you face microwave. There are three screws on the bottom right edge to loosen. After that the side panel slips down and off. the fuse is located in the rear near where the power cord comes in. It is the white ceramic tube 1/4" in dia. and 1-1/2" long. Pull it out like any fuse and replace with new one. Reassemble and you are done!

I followed an old appliance repair forums post from 2008 that discussed this exact common issue with this LG model. It took me quite a while to find the info. Then I used the schematic diagrams on your website to find where the part was located inside the microwave. I removed the outer cover. I tested all components including the thermostat for continuity with a multimeter. I discovered there wasn't any continuity in the thermostat so ordered the part and replaced it. Everything works like a charm! Thanks for the great, fast service.

Remove the rear casing of the microwave using both a Phillips head screw driver. The lower rear screws require a star shaped bit with a hole in the middle (security bit). Once the rear casing is removed, it is very easy to access and replace the bulb. But the bulb sent was NOT identical to the original which has a straight fitting into the receptacle. The one sent had a fitting with a 90 degree. The bulb did not quite fit in place, but I secured it with some black electrical tape.

I want to preface this review by stating that I do some DIY from YouTube, but have no experience in electronic repair. The microwave is over the stove with the extendavent. First I unplugged the microwave, removed the vent and started to unscrew the microwave from the mount. I used a power drill to speed things up. I was able to remove the microwave on my own. I unscrewed the lid on the microwave and took the lid off and there is the magnetron. I opened up needle nose pliers to have each end touch the terminals of the capacitor (holds the power, Dangerous). I made sure to keep my hands on the rubber handles and avoid touching the metal part of the pliers. I used the pliers to remove the plug of the capacitor to the magnetron as well. The magnetron has 4 screws (2 top, 2 bottom). There is a magnet that can hold the screws to keep from falling but I’d still recommend a screwdriver with a magnet on the end. The magnetron has another set of wires connected by a metal bracket like a holder, not really connecting any wiring to the magnetron itself. I had to unscrew 1 screw to removed that. Adding everything back on was easy, same steps back. I plugged in the microwave and tested a cup of water before I mounted it back above the stove. Voila! I did need my wife’s help to hold the microwave on the hinge while screwing into the mount. It doesn’t take a lot of muscle for the help. $85 for the part and ~40 mins to fix a $400 microwave!

Remove from cabinetry, take cover off and had a very difficult time removing the plastic form that has the switched in. Replace the lowest of all the switches, and then again very difficult time getting the plastic form back in. Some of the plastic even broke during the process but not any that could prevent it from working as it did before. I had ordered a fuse, 2 packs of 2 switches as there are 3 switches but only had to use 1 to get it working again. Tested after switch install, put the cover back on and reinstalled in the cabinet.

I verified I had 120 volts going into transformer when the microwave was supposed to be running. The capacitor and HV diode both tested good. Be sure to discharge the capacitor before working in this area. This isolated trouble to either the transformer or magnetron. The windings of the transformer measured good. So ordered a magnetron. It was very easy to swap. There were 4 screws and one connector. This fixed our microwave.

Used a Motor cycle Jack to remove both unites combined. Removed side panels exposing internal working parts. Removed nonworking Magnetron and replaced it with new Magnetron. The process was completed in about 1 hour.

unplug the unit then pull down , lot of screws are on top. open the cover . you could see the parts that need to replace on the right hand side (heavy side). disconnect wires then test the parts that need to replace by a tester to make sure that it's really broke .then unscrew part and replace .

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.

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.

hardest part was taking the microwave down off of the wall to gain access to the diode. Thought if was the transformer but ended up being just a blown diode. remove and replace and bench test. that part took 15 minutes . moral of the story don't boil water under the side of the microwave that holds the electric components.

Received my replacement Tray,Glass in only 2 days. Opened it and placed it in the Microwave. Yep, it was that easy!

My wife was pushing a few buttons with her knuckle (hands were full)and the microwave just turned off. Just like we had blown a breaker. First I unpluged it. Then I removed the phillips screws of the front panel, and found and removed the ceramic fuse. 3 days later I received the new fuse in the mail, and put it in. I plugged the microwave back in and it works great.