On and off the fridge wouldn't defrost properly

Did the troubleshooting with online instructions and a multimeter. Bought the new thermostat. Disassembled the freezer compartment using a nut driver to expose the evaporator, etc. The thermostat was easy to locate in the upper right hand corner. The new thermostat had one wire that didn't have the correct connector on it so I stripped the wire back and used a crimp connector and heat shrink to attach the connector from the failed thermostat. After plugging the new thermostat in I ran the refrigerator for 15 minutes to cool the thermostat and then rotated the defrost timer to the defrost position and tested the new thermostat. Reassembled the freezer compartment.