My last fridge literally had the ability to press some buttons to get error information as an encoded sound. An app is used to decode the audio to obtain something that can be read. Sadly it was a break in a component that cannot be swapped out.

I've fixed appliances, and the best source of information about what is wrong is usually the microcontroller. Sometimes it's just a hex error code, and that's enough. A firehose of text like MacOS currently produces is unusable.