Hello, You can have your thermistor replaced. You may have two of them, one inside the wall of the fridge that monitors the temperature of the fridge and one attached to the cooling coil. This thermistor attached to the cooling coil is most likely the culprit. it does not send the signal for the computer ( mother board ) to initiate defrost that is why the ice builds up on the cooling coil and migrates to where the blade is and prevents the blade from turning later on.
Observe it for a few days after replacing the thermistor. Let me know what happens.
We thought so, too, and have already ordered a new thermistor. We did not realize that there are 2 of them, so that is interesting to know.We will let you know if it solves the problem.
Ok. I hope it would solve your problem by then. Thank you for using this service.