How to Troubleshoot & Replace Ge AP2025948 / WB27X10037 Diode Assembly

I took the advice of another buyer and replaced the magnetron, capacitor, and diode from my microwave (make sure you discharge the capacitor). It was not a problem at all to do, I did find an excellent video on YouTube on how to test all of these components and almost anything else in a microwave. It’s called Microwave Oven Troubleshooting in Minutes- Step by Step by electronicsNmore. It was the best thing I watched. Turns out my magnetron was the only thing that was bad and it’s the most expensive part, so replacing the other too wasn’t a big deal. My microwave really heats well now. I guess it had been getting bad for a while. I might get add, my microwave was a $1500 GE MONOGRAM microwave/convection oven so spending a couple hundred for parts was a no-brainer, but had it been a cheaper $300-400 model, I would’ve just bought another one. Matching the appliances in my wife’s kitchen was also key. I might also say, that although I’m handy and do have some electronics experience, I built my own tube guitar amps years ago, I am a counselor by trade, and doing this project taught me how a microwave works. It was fun to learn, and easy to do. Watch the YouTube video before you remove one screw. You will learn a lot, and also see a professional be extremely careful while discharging the capacitor. 1000 volts is nothing to play around with, but the capacitor does have a discharge resistor built-in and mine was discharged when I tested it, and although the video shows you how to build a discharge rig using a ceramic resistor, which is the safest way to go, I don’t personally think it’s necessary. He shows other ways to discharge too. This is the most important thing to do in this repair. 

Instead of wasting time troubleshooting, I purchased the 3 components suggested that could be the cause for the issue (magnetron, diode and capacitor). Replaced all 3 components and now I once again I have heat. Job was really easy except for trying to install the screws around the magnetron - kept getting sucked up by the magnet. Great website and parts arrived as quickly as advertised. 

This GE Microwave oven is no longer being manufactured and was installed along with a $300 trim kit, so I really didn't want to change out the unit since the trim kit is proprietary. Disassembled microware, looked at the schematic attached to the inside of the unit, made sure capacitor was discharged. Checked the flame sensor and diode- they tested bad when tested with volt/ohm meter. Ordered parts- they came two days later. Replaced flame sensor and diode. Panel powered up. Still no power to magnetron. Had to remove oxidation on low voltage side of transformer terminals where wires attached. Reattached the wires to the transformer Then magnetron started humming, and heated water. Reassembled unit and re-enstalled. 

This was much easier than I expected. First and foremost discharge the capacitor, google has the instructions. The diagnosis was also easy, really just 3 parts, the Magnetron, the Capacitor, and the Diode. With a simple multimeter measuring the resistance I was able to determine the Magnetron had shorted out and the diode was bad. I replaced all three components which fixed my issue. 

REMOVE AND REPLACE: MAG. CAPACITOR AND DIODE 

Replaced upper latch micro switch. (After removing the Advantium from the wall and removing the cover, all four fuses, the diod, and Magnetron tested okay with a multimeter. The upper latch micro switch was visibly defective - the spring function no longer worked.) 

Swapped Magnetron. Pulled microwave by removing the 4 mount set screws into cabinet by opening unit door. Turned off breaker. After sliding mw out, removed top cover plate 2 screws only. Once cover removed, Magnetron clearly accessible. Take a picture of wiring. Removed insulated wiring terminals from each side(2 sides). 1 pair on magnatron, 1 pair on thermostat. A magnetized phillips screwdriver is almost required for this job to remove the 4 screws mounting the magnetron and to remount. Screwdriver should be at least 8-10 inch or longer flex type. Dismounted small button type thermostat and mounted it on the new magnatron. Reinstalled magnetron, replaced wiring, replaced cover, tested microwave before reinstalling in cabinet. 

First off this appliance is 16 years old. The replacement machine is no longer made in the color we need, also the new ones rated very poorly. After taking the appliance apart I discovered the high voltage capacitor had been leaking, probably the odor I had been noticing. I had decided in advance to replace as many parts that made sense to restore it as close as possible to its original state. Replacing the turntable motor was very easy. The magnetron, capacitor and diode was a little more time consuming but not to tricky. Be sure to use needle nose pliers with good rubber handles to discharge any stored electricity in the capacitor. Do this before before disconnecting the magnetron. You will also need a security torx bit to remove the cover, regular torx bits won’t work. It took a little longer as this appliance is built into a wall cavity. 

Purchased magnetron and diode 

Replaced magnetron and diode ass'y. This is a hanging over the range style. Best to have a buddy to help lift out and rehang. A screw gun and a short extension makes this a breeze. Tested before re-mounting. Unit boiled water in a minute! Customer service via on-line chat was excellent.