I am having the standard defrost control issue where the coils are freezing because the defrost system is not working correctly. I am relatively certain that the problem lies with the adaptive defrost control board, and I am planning on replacing it. The part is on order now.

The interesting part is that, when I was ohm-ing out the heater and defrost thermostat, I noticed that the wiring appeared to be slightly different than shown on the wiring diagram. The blue wire coming from the temp control was connected directly to the heater element and the Yellow wire from the adaptive control board was wired to the thermostat. Essentially, it looks like the heater/thermostat is wired backwards (relative to the schematic). The plug can only go in 1 way, so this would have to have come from the factory this way.

My question is... Is this a problem? Or since power can't flow unless the thermosat "closes" and completes the circuit, it doesn't matter f the element comes before the thermostat in series?

The fridge has had this problem basically since we got it used (very cheap) last summer. I do not know if the defrost system ever worked. It has not been a major problem for us as the coils don't seem to freeze up much during the winter.

Based on the fact that the defrost board uses the wh/bk wire to sense when the heater needs to turn on, sounds like I need to switch the wiring to match the schematic. Would that be your suggestion?

So the wiring is definitely backwards... I got a new heating element today and installed it. The plug is wired opposite from the old one. The current installation now matches the schematic. I will keep you posted on if this fixes all my woes (at least my refrigerator woes).

Thanks for all your help.