My trusty 18 year old GE just shot craps. It beeps and junk on the display and I also found a reference to my problem in the EURAS database, but they want me to pay for the info. It beeps and kinda freaks out. The boards in it appear fine, no cold solder joints or burned components. I found a small sheet of diagnostics inside the case, and the only thing I tested was the TRIAC, and it reads 50ohms not the 70 listed on the sheet. Other than that, I don't know much! What I found was this:
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It's a Model JE2800-001, any help appreciated. Please copy me via email if you have an idea of what to try.
Try unplugging it for a while, then plugging it back in. Maybe the microprocessor is confused.
You might check the fuse, but it probably isn't blown if you can get some action out of the oven.
Check the interlock switches. There will be at least one that is designed to open with the door unlatched - it will either interrupt the line voltage or serve as an input to the controller board. Usually, there is also a switch that is designed to "crowbar" directly across the hot and neutral lines and blow the fuse.
There should be a small power transformer on the circuit board; check the AC voltage(s) on its secondary. Typically these have a pretty simple linear power supply on the board and you may be able to tell if the DC output is low. If you have a scope, look for excessive ripple (bad filter cap) on the DC output.
Been unplugged for over a day, was hoping that was it myself. I'm getting garbage sometimes, so thinking voltage may be screwed up, I'll check the transformer.
I testing the transformer that supplies the PCB, output is 2.5V and 14V AC, close enough to match what's posted. With that and that alone plugged in, it gives me a beeping and garbage on the display, so I'm down to narrowing something down on the so called "Smart board" or replacing.
What I would suggest first is to replace all of the electrolytic capacitors on the smart board. They may be black, green, blue, etc., and look like those seen in the photo here:
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What happens is that the electrolytic (liquid) wears out, changes pH level, or dries out over time, and they stop filtering the rectified DC voltage from the power supply. The fluctuations (noise) that get through will drive ICs crazy! New caps may fix this for you.
To get the replacements needed, you can visit Tritronics at
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Be sure the value of the caps you order is the same. Voltage can be a step higher. These are all 105-degree caps, and very good, too. Be sure the plus-minus polarity is the same when you install the new ones or they can actually pop and take off like little rockets! Safety first!
Also, I would recommend resoldering and if possible actually testing any parts which are burned or which have darkened spots under them on the circuit board. Big transistors and resistors are your first suspects. They can desolder themselves over time as the solder experiences metal fatigue from the heat.
Lastly, look for brown glue (goo) used to hold components down before they were machine soldered during manufacturing. This glue can become conductive over the years, causing odd and aggrivating problems.
Still need help? I fix microwave control panels for only $32.50 in most cases. See
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Good luck, and observe safety rules (such as those at
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