Dave C. for Model Number PSI23SGNAFBS The freezer iced up and temperature went up to 28° or so. Refrigerator side went up as well. Defrosted it and replaced the defrost heater and turned unit back on. It iced up right away. I checked voltage from the motherboard to the defrost heater at tab 2. There is no voltage on that tab. The compressor tab (1) and ice maker tab 4 have voltage. Is this a bad board? I have checked all the pin to pin according to the Service guide. Should there be voltage on TAB 2 always?
Answer Hello Dave, Voltage will only appear on tab 2 when the unit cycles into defrost. The compressor will never be energized at the same time as the defrost circuit. The most common cause of a defrost issue on this design is the defrost heater WR51X10055. The defrost thermostat WR50X10068 should be tested for continuity also. The control board WR55X10942C is normally the last suspect but can also cause the defrost issue since it determines when the unit will cycle into and out of defrost. Read More... Answered by AppliancePartsPros.com | Thursday, August 25, 2016