The fridge has worked great for around 8 years. This week the fridge started to warm up but the freezer was fine. I ran diagnostic tests and everything seemed fine except no flow through damper. I pulled the freezer drawers and panel and found evaporator coil fully iced over. I left it open for a day to thaw and put it back together. Everything seems functional but evaporator fan is always on.

Prior to reassembly I checked defrost heater (~29 ohms) and the defrost thermostat (open when warm, shorted when cold). I believe these components are good. I am concerned that the fan should not be constantly running and I don't know why it didn't defrost. From reading, I believe I need to replace the JAZZ board. Does that sound like the next step or am I missing something first? Second, how do I access the JAZZ board for testing? I can't find any directions on removing the cover in the fridge without breaking it. Also, if it's a bad component on the board, is there any chance it can be repaired rather than replaced? $0.10 resistors are cheaper than $150 logic boards!