The customer called about an error code on the display of their LG refrigerator. The user interface wasn’t working the way it should — they couldn’t even switch the dispenser from ice to water.
This error code means there is no communication between the user interface board and the main control board.
We started by disassembling the dispenser and removing the freezer door hinge cover.
The user interface is connected to the main control board by a 4-wire harness. We checked every wire and found that one of them — the one responsible for data transmission — was broken inside the door.
The user interface harness is only sold together with the freezer door, and that assembly costs around $500.
After checking the wiring diagram, we offered the customer an alternative: if they were OK with giving up the dispenser light, we could use its wires to restore the connection to the user interface. The customer agreed to the modification.
We fixed the malfunction by using the dispenser light wires for the data line.
The fridge works fine!
Want to see a similar diagnostic in action? Watch our video LG refrigerator Er CO error code diagnostic and repair on YouTube.