Thank you for asking this question and allow me to answer it this way.
That fridge uses thermoelectric technology to cool. It uses what is called a "peltier" chip, which basically takes heat and moves it from one side of the chip to the other when electricity is applied. If you reverse the polarity applied to a peltier chip, the cooling system, the opposite sides will get hot/cold respectively. In other words if you were to reverse the polarity of that you could in effect make the fridge a warmer and the heat sink would blow cool air.
The reason yours is not cooling is most likely because of that fan not spinning fast enough to dissipate the heat on the "hot side" of the peltier, the cooling system. If the heat cannot be taken away the, cold side, it will not get cold. Try spinning the fan by hand, does it spin freely? If so it is a power/voltage issue, which would also contribute to the problem, if the peltier is not getting enough volts/amps it will not work correctly. If the fan is difficult to spin or seems like its binding up or sticking, the bearing is most likely bad and it will need to be replaced. The voltage is 12v. You can also test the motor if you have a multimeter by setting to the dc volts scale and measuring what is coming out of the 2 pins. There is no diagram for this. It was never released.
Here is the link for the parts
Kenmore Compact Refrigerator 461.91782
NOTE: Always unplug or de-energize electrical equipment before removing covers or attempting service.
Be careful and wear appropriate hand protection when working around sharp metal parts.
I hope this answer is useful and that it helps you correct the problem with your appliance.
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