How to Troubleshoot & Replace Whirlpool AP4009169 / 12002355 Thermistor Kit

Replaced the thermistor and bingo! 

Thanks for everyone’s shared experiences to help fix my warm Kenmore Elite 596 fridge. Freezer worked fine, fridge was room temp. I bought a new thermistor after cleaning the gunk out from underneath and behind the unit, confirming the compressor and condenser fan were working. The video was very helpful in replacing the thermistor and that went smooth, but that didn’t fix the problem. I took apart the vent in the back of the fridge to expose the damper door, which was closed. I wedged a fork under the door and cold air started to pour into the fridge. I tapped on the control arm that moves the damper door with a servo and it moved. I’m guessing the control arm or servo was maybe stuck in place and needed a little nudge. I’m still keeping an eye on it but after a week I still have a properly functioning fridge. May need to replace the cold air damper next. Used a flathead screwdriver to remove plastic covers within fridge, a Swiss Army knife to trim insulation off the wiring, and some pliers...and a vacuum. Going to clean under the fridge a little more regularly now. 

Just one of the parts they did have would have cost me $280 (damper motor) not including labor. I bought all 4 parts - damper motor, thermister, defrost thermostat and drawer gear kit - for $167 delivered in 2 days. The serviceman installed them in about 1 hour and charged their hourly rate of $125. So, for a total parts and labor of $292, a little more than what they would have charged for only 1 part the fridge was fixed. I'm very pleased. 

Unable to get a new refrigerator due to COVID, found a nice counter-depth used model but after purchased noticed it was not holding temperature and the damper control had been damaged. Installation of the Thermistor and Damper Control assembly was extremely straightforward and now the refrigerator is working flawlessly. 

Replaced parts after we let the fridge thaw out. 

By using your repair videos and troubleshooting suggestions I was able to determine the problem and order the correct replacement parts. I really appreciated your next day delivery of parts, problem was solved in 24 hours! You folks are the best! 

I was on the appliance parts pros site buying a lint filter for a dryer. I entered the model # for the fridge out of curiosity just to compare the price of a part I purchased a couple of years ago some place else. I clicked on the troubleshooting tips and I saw one that says if the refrigerator is too cold, change the thermistor and an attached video showing you exactly how to change it. I ordered the part, got it super fast, changed it that same night. Now my fridge is back to normal. I'm elated with joy. Thank you and keep up the awesome work you do. God bless. 

We ordered the part and replaced it. 

Replaced the Control Board for the 2nd time, but also replaced the fridge thermistor, just to be safe. The 1st time was less than a year ago, but was not an OEM part. This time we replaced it with the OEM part, so hopefully will last longer. 

Purchased a new thermistor. Used a kitchen butter knife and wire strippers for the job.