Several years ago our near new but out of warranty refrigerator quit.  I diagnosed the problem and called the dealer to order the replacement part.  IIRC it was a $160 REFURBISHED circuit board.  In the meantime I took out the suspect part and started inspecting it.  It had a standard round, 1" glass 5 amp fuse soldered onto it that was blown.  It was nearing closing time for the coop but I hurried there and got a fuse.  It took me a few minutes to replace the fuse but last I knew (sold house) the refrigerator was still going.  50 cents as opposed to $160.