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So the error OP means that the freezer temperature sensor inside the freezer has failed. This could have been from water getting on it when you were defrosting it, or possibly the heat from the hair dryer. Either way the freezer temperature thermistor will need to be replaced if you find it's securely plugged in. Below is a link to the part you'd need to order and replace for your model.
CLICK HERE for freezer thermistor sensor
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