LG
FM4FBM30SS
Refrigerator
LG FM4FBM30SS — Error Code Er CO
LG FM4FBM30SS error code Er CO: Communication error between boards.
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Last updated:
Methodology: We combine manufacturer references with recurring service patterns, then review for safe, step-by-step repair guidance.
Sources: Manufacturer fault-code sheets, service manuals, and recurring field-repair patterns.
Limits: Guidance is informational and may not match every model-year or revision. Confirm with the official manual and diagnostics before replacing parts. For safety-critical or electrical work, use a qualified technician.
Looking for the full diagnosis and repair guide? View complete LG Refrigerator error code Er CO guide →
Repair guidance: the symptoms and steps below come from the canonical LG Refrigerator Er CO guide and apply to FM4FBM30SS unless your manual says otherwise.
Symptoms on FM4FBM30SS
- ⚠️ Error code on display
- ⚠️ Temperature not maintained
- ⚠️ Unit making unusual noise
How to Fix Error Er CO on FM4FBM30SS
- 1 Unplug the refrigerator for 60 seconds then plug back in — this resets the control board and clears many temporary faults
- 2 Check all wiring harness connections to the main control board — reseat any loose connectors
- 3 If the board shows burn marks or damaged components, replacement is needed ($80–$300)
- 4 If the error persists after basic troubleshooting, contact a qualified appliance technician
🛠️ You'll need: Screwdriver set, Multimeter
· Time: 30–90 min
Questions People Also Ask for Error Er CO
What does LG Refrigerator error code Er CO mean? ▼
Error code Er CO on a LG Refrigerator means: Communication error between boards. The appliance detected this condition and has stopped or limited operation to prevent further damage.
How do I fix LG Refrigerator error code Er CO? ▼
First, unplug the refrigerator for 60 seconds to reset the control board. If error Er CO returns, the root cause (communication error between boards) needs to be addressed — check connections, filters, and hoses before calling a technician.
Is it safe to use my LG Refrigerator with error code Er CO? ▼
It depends on the cause. Most Er CO errors mean the appliance has stopped itself as a safety measure. Check the 'Should I unplug it?' section above for specific guidance on this error.