I have an 11 year old GE Monogram side by side built-in fridge that had been having cooling problems intermittently. The fridge would work for a day and then the compressor would not come on for 8 hours and temps would rise to the upper 20s in the freezer. Fans, lights, and everything else appeared to be functioning properly. It went like this for a few weeks and we put it off until the compressor decided not to come on at all for a full day.
Being barely able to use a multi-meter, I watched a bunch of YouTube videos on how to troubleshoot the motherboard and inverter. I read 5.2v from j15 on the motherboard and ruled it out. Also confirmed 120v from the line coming into the inverter board.
Messing with the inverter was the most intimidating but once you know how to take it out, it actually takes less than 5 minutes take off and on and all you need is a screwdriver. Once I had the inverter out, I ohm'd out the 3 inputs on the compressor and got 6.7 on all 3. Visual inspection on the inverter wasn't conclusive but from what I've read the most likely culprit at this point is the inverter.
I ordered the inverter on Thu morning and it was in my hands Friday morning around 10am. The inverter I received wasn't the grey box pictured. It was black and had a metal plate visible in the back. I was also concerned that it was only rated to 133Hz while the previous one and the label on my compressor shows 150Hz. The voltages did line up and the model number did match the order and it came in a sealed GE package. I'm assuming GE re-designed it sometime in the last 10 years.
It plugged in without any issue using one of the supplied dongle cables for the motherboard input. As soon as I turned the fridge back on, the compressor came on without a hitch. I took the old inverter apart and noticed the two large capacitors were blown confirming the problem.
I'm happy to report the fridge has been running for a few days and appears to be cooling as expected but would love to know if there's an older inverter board that would be a better match for my compressor.