I fixed a malfunctioning refrigerator by replacing the control board, which happened to be a PIC16-based device used by many brands. This design is as close to "universal" as you can get, and this generic board was around 20% the price of the official replacement part.

https://www.ebay.com/itm/152763501102

That's because many different brands are actually made by Whirlpool. They're like the GM of the appliance industry.