What does Er CO mean?
The display board and main board are not communicating.
Common causes
- Loose connector
- Wiring damage in the door hinge
- Board failure
What you can safely check
- Power-cycle the refrigerator for 1 minute
- Schedule service if it returns
Safety first. Unplug the appliance (and shut off gas or water where relevant) before inspecting it. Codes and procedures vary by model — check your owner’s manual.
When to call a technician
If the code comes back after these checks, or you see leaks, burning smells or tripped breakers, stop using the refrigerator and schedule a technician. Our team repairs LG refrigerators every week.
Frequently Asked Questions
What does LG refrigerator error code Er CO mean?
The display board and main board are not communicating.
How do I fix LG code Er CO?
Power-cycle the refrigerator for 1 minute. Schedule service if it returns.
When should I call a technician?
If the code comes back after these checks, or you see leaks, burning smells or tripped breakers, stop using the refrigerator and schedule a technician. Our team repairs LG refrigerators every week.
Other LG refrigerator codes
Er CFCondenser fan errorEr dHDefrost heater errorEr FFFreezer fan errorEr IFIce maker fan errorEr rSRefrigerator sensor error
Updated Oct 29, 2026