Problem:
Temperature is displayed in Celsius.
Solution:
To switch it back to Fahrenheit, please follow these steps.
1) Thermometer has to be turned OFF.
2) Push and hold the "Ear" button.
3) The thermometer will display a "M" in the lower right corner, do NOT let go of the "Ear" button, keep it pushed until you see a "C" flash.
4) Let go of the "Ear" button and then short press it one more time. The "C" will change to a "F".
5) Wait until thermometer turns off which will save the Fahrenheit selection.