Kenmore fridge 596.79323010 not defrosting automatically

[shillion]

This fridge is very close to GX2SHBXVY05 which uses the Jazz board. But the Kenmore one uses a different board. This Kenmore 596.79323010 010 has more controls such as door alarm, water filter warning, etc. So the control board is different. In a Jazz board machine, if the diagnostic can defrost the evaporator which means the heater, defrost thermostat, the thermistors are good, I would definitely replace the Jazz board. Now this Kenmore one behaves the same, in diagnostic, defrost OK, thermistors are good, should I replace the board as well, just like the Jazz board? I never replace this board before. Please help!

[Dash]

Holy cow, I've replaced lots of electronic control boards on Whirlpool built bottom-freezer refrigerators in the past 15 years.  Most commonly I replaced them because the defrost function wasn't working.

[shillion]

The reason I am not sure is this board is expansive. Other cases, I only replaced the freezer evaporator thermistor even though it tested OK at the analytical process. May be I should replace the thermistor only.Did you also replace the thermistor as well?