LG Refrigerator Error Code Er CO
Communication error — main board to sub-board
The main control board cannot communicate with the display or sub-control board.
What Does Error Code Er CO Mean on a LG Refrigerator?
Communication error — main board to sub-board.
The main control board cannot communicate with the display or sub-control board.
What Causes Error Code Er CO?
Here are the most common causes in order of frequency. Start with the most likely cause before moving to the next:
- 1 Wire harness connector loose between boards 55% of cases
- 2 Sub-board failure 30% of cases
- 3 Main control board communication fault 15% of cases
How to Fix LG Refrigerator Error Code Er CO
- 1
Power cycle
Unplug 10 minutes.
- 2
Reseat all connectors
Check all multi-pin connectors at both boards.
- 3
Replace sub-board
Cheaper than main board to try first.
🔩 LG refrigerator sub-board ($60–$150)
How to Reset Error Code Er CO
Unplug 10 minutes. If Er CO returns, check all connections.
Note: If the error returns after resetting, the underlying issue has not been resolved. Work through the fix steps above.
When to Call a Professional
If both boards replaced and error persists, wiring harness between them has failed.
Related Error Codes
Find Replacement Parts
Use these links to find the exact replacement parts for your LG Refrigerator:
External links — ApplianceErrors.com is not affiliated with these retailers.