Took the freezer apart 4 times until we got the fuse replaced. First thought it was the evaporator fan but that was working fine. A week later ice build up and fridge would warm again Finally, got a multimeter and tested each suspect for proper continuity and resistance according specs found on the web. Now defrost is working again. Hardest part was the diagnosis then wading into the unknown -as in how does this evaporator come out. Videos will get you there. Now I’m super glad I saved beaucoup bucks!