The part links posted are for your specific model.
Solution 1:
Condenser Fan Motor
The condenser fan motor draws air though the condenser coils and over the compressor. If the condenser fan motor is not working properly, the refrigerator won’t cool properly. To determine if the fan motor is defective, first check the fan blade for obstructions. Next, try turning the fan motor blade by hand. If the blade does not spin freely, replace the condenser fan motor. If no obstructions are present and the fan blade spins freely, use a multimeter to test the fan motor for continuity. If the condenser fan motor does not have continuity, replace it.
LG Refrigerator Condenser Fan Motor Assembly - 4681JB1029D
Solution 2:
Evaporator Fan Motor
The evaporator fan motor draws air over the evaporator (cooling) coils and circulates it throughout the refrigerator and freezer compartments. Some refrigerators have more than one evaporator fan motor. On refrigerators with only one evaporator, the evaporator is located in the freezer compartment. If the evaporator fan is not working, it will not circulate the cold air to the refrigerator compartment. If this occurs, the freezer may still get cold, while the refrigerator will not get cold. To determine if the evaporator fan motor is defective, try turning the fan blade by hand. If the fan blade does not turn freely, replace the fan motor. Additionally, if the motor is unusually noisy, replace it. Finally, if the motor does not run at all, use a multimeter to test the motor windings for continuity. If the windings do not have continuity, replace the evaporator fan motor.
LG Evaporator Fan Motor - 4681JB1027C
Solution 3:
Start Relay
The start relay works in conjunction with the start winding to start the compressor. If the start relay is defective, the compressor may sometimes fail to run or may not run at all. As a result, the refrigerator will not be cold enough. To determine if the start relay is defective, use a multimeter to test it for continuity between the run and start terminal sockets. If the start relay does not have continuity between the run and start terminal sockets, replace it. In addition, if the start relay has a burnt odor, replace it.
LG Refrigerator Compressor Start Relay Thermistor Assembly - 6749C-0014E
Solution 4:
Compressor
The compressor is a pump which compresses the refrigerant and circulates the refrigerant through the evaporator and condenser coils. If the compressor is not working, the refrigerator won’t cool. However, this is rarely the case. Before replacing the compressor, first check all of the more commonly defective parts. If you have determined that all of the other components are working properly, check the compressor. Use a multimeter to test the continuity between the electrical pins on the side of the compressor. If there is an open circuit, the compressor is likely defective. If the compressor is defective, it must be replaced by a licensed technician.
LG Refrigerator Compressor - TCA37091209
Solution 5:
Main Control Board
The main control board might be defective. However, this is almost never the cause. Before replacing the main control board, test all of more commonly defective parts. If none of the other components are defective, consider replacing the main control board.
https://www.repairclinic.com/PartDetail/...
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To help You id need to know if the freezer fan , the condenser fan and if the compressor wereall working? Do you notice frost inside the refrigerator anywhere? Any water leaking? Is the compressor hot to touch?
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It's been my experience that your situation is caused by the evaporator fan (freezer) fan not working. There are any number of reasons for that but here are two preliminary steps. First check if the fan comes on when you open the freezer; if not you know you have some sort of fan issue. Second, if-and only if-you are comfortable with live power, you could try resetting the unit. What follows are my LG experience-you should check for a manual online as to the details of this step. If there's a rear panel labelled "hazardous" the unit's circuit board ("ECB") is behind the cover. Unplug the unit, remove the screws, and look at the board. There should be a small button marked "test" somewhere. Plug the unit back in, wait for the compressor to kick in then press the button once. Wait another minute, press it again and the unit should shut off. Unplug it, wait 5-7 minutes and plug it in again. This may reset the board so that the fan will operate correctly.
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