How to Troubleshoot & Replace Samsung AP4308802 / DA32-00006S Refrigerator Temperature Thermistor

The evaporator keeps freezing up, this has been an ongoing problem with this refrigerator. I have paid for the extended warranty many times with the promise of refrigerator replacement if the problem keeps happening. That being said I have watched the Techs tear the refrigerator apart several times to thaw out the evaporator and replace the fan unit 3 times. The warranty expired and we refuse to pay to extend it again. By ordering the parts from AppliancePartsPros.com it was cheaper and quicker to get the parts and repair the refrigerator myself as opposed to paying for the warranty that has too much fine print that exempts the company from following through with what they verbally say they will do. 

Figured out that it could be the sensor temperature, now the fridge works like a brand new one. Thank you for sent me the right part . 

In October, I replaced one of the sensors behind the panel inside the refrigerator (I don't know what that part was called. With the refrigerator defrosted, the temp came down and stayed that way until January. In early January, the ice started building up again. This time I replaced the thermostat and thermistor. After defrosting the freezer and removing the trays, screws, and back panel, I disconnected the wires from the back and replaced the sensors with the replacement sensors. The video on the website made it easier, I just followed that and put everything back the way that it was. It's been over a week with no ice yet. 

The evaporator cover (includes fan & motor)and the several defrost parts. 

Your video on replacing the sensor made the task SO easy. Thanks! 

Replaced all 3 parts 

Followed youtube video to Replace defrost thermostat. 

Replaced the defrost heater, thermostat and thermistor. 

After doing some research on this issue, it was apparent that the defrost thermostat, and possibly the Temperature Thermistor were bad. Since I was going to go through the work of defrosting the fridge and removing all the drawers and shelves, along with the rear panel (inside the fridge) also known as the evaporator cover, I ordered both parts. Overall, this was not a difficult job. What took the longest was fully defrosting the fridge ensuring the ice buildup behind the evaporator cover was all melted (~ 24 hours) and then removing all the shelves and drawers. Replacing the two sensors was a snap. I always take before, and after pictures, with my iPhone's camera. That way, there is no mixing up what goes where. You will need a Philips head screwdriver, a flashlight or headlamp, some small tie wraps (to dress up the cabling), and wire cutters (to cut the tie wraps). The video that AppliancePartsPros.com provided is very good and straightforward. 

Installed both sensors, this fixed the problem.