er co
Moderate
LG · Refrigerators
Communication Error
Quick Answer
Error code Er CO on your LG Refrigerators means: Communication Error. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. Communication failure between the main control board and the display board
  2. Wire harness between the boards is damaged, pinched, or disconnected
  3. Main control board has a faulty communication circuit
  4. Display board has a faulty communication circuit
  5. Power surge caused corruption on one or both boards
How to Fix It
1
Unplug the refrigerator for 5 minutes to reset both control boards
2
If the error returns after power-up, access the main control board (bottom rear) and the display board (top of door or behind the control panel)
3
Check the ribbon cable or wire harness connecting the two boards for damage, pinched wires, or loose connectors
4
Reseat all connectors firmly at both boards
5
If the harness is intact and error persists, replace the main control board first, then the display board if needed
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Main control board (model-specific LG part)
Display control board (model-specific LG part)
Communication wire harness
Related Error Codes
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