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Open the refrigerator and tell me if you can feel cool air being circulated into the refrigerator. Feel around the top of the frige section for this.That is where it will be strongest.
Also need to know if there is any frost build up ast the back of the freezer section (inside not outside).
Ok you probably have an automatic defrost system that has failed.
What you can do is use a hair dryer and direct the warm air into the louvers/vents of the freezer compartment. Run it for at least 15 minuets. That will manually defrost the evaporator coils behind the back cover of the compartment and allow air to Be blown over them by the freezer fan and into the refer section.
If that works then you will need to call for service. This is not a job for an untrained person. If you test the wrong circuit you can cause more damage than good.
The manual defrosting can be done multiple times if you need to. Each defrosting will give you about 5 days of proper cooling before things start to ice up again.
If the evaporator cpoils are iced up no air can be blown over them by the evporator fan (freezer fan). If the air cnt be blown past the coils it wont make it to the refrigerator section.
All of your units cooling comes from the evap coils at the back of the freezer section.
There is an air damper at the top of the refrigerator. That is the only other thing that would stop the air flow. It is electronicly controled and besides the defrost system components it is the next biggest failure in this model series.
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