Er rF Error Code Online Training Manual for LG Products - Refrigerator Fan Error      
errf_0
errf_1 Does the Er rF error code show on the display?
errf_2 Unplug the refrigerator and check CONNECTOR 4. Check for bent pins and broken wires, then reconnect it and power up the refrigerator.
errf_3 Power up the refrigerator and enter TEST 1 MODE.

Read the voltage across PIN 3 (BL/WH) and PIN 4 (GY). It should be 12 ~ 16 VDC. If not, replace the MAIN BOARD.
errf_4 Still in TEST 1 MODE, check the top vents of the MULTI-DUCT for air flow.
errf_5 Still in TEST 1 MODE, if there is no air flow, remove the MULTI-DUCT and check the fan motor. Check the connector and make sure the motor turns. Replace the motor if it is locked.
err_6 Still in TEST 1 MODE, check the voltage across PIN 4 (GY) and PIN 5 (YL/BK) of CONNECTOR 4. It should be 1 ~ 4 VDC. If not, replace the MAIN BOARD.

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