ER DM
LG Refrigerator
Severity: ModerateWhat Does This Error Mean?
The ER DM error means your LG refrigerator's defrost sensor has detected a fault. This sensor monitors the temperature of the evaporator coils during the defrost cycle. Without it working correctly, ice can build up on the coils and eventually stop the refrigerator from cooling.
Affected Models
- LRMVS3006S
- LRFVS3006S
- LRMDS3006S
- LFXS26973S
- Most LG French door and side-by-side refrigerators
Common Causes
- Defrost sensor (thermistor) has failed or reads outside its normal resistance range
- Loose or corroded wiring connector at the defrost sensor
- Ice buildup over the sensor probe, affecting its readings
- Defrost heater assembly fault preventing the defrost cycle from completing
- Control board unable to read the sensor signal correctly
How to Fix It
-
Check if the refrigerator is still cooling and the freezer is still freezing.
If temperatures are still normal, the fault is early-stage. You have time to arrange a repair without urgent food safety concerns.
-
Manually defrost the refrigerator.
Unplug the unit and leave both doors open for 24–48 hours. Place towels on the floor to catch melt water. This melts any ice that may have built up over the sensor. Plug back in to test.
-
After the manual defrost, plug the refrigerator back in and monitor for 24 hours.
If ER DM clears and cooling returns to normal, the ice buildup was the cause. The underlying sensor fault may still exist — monitor for the error to return.
-
If ER DM returns after manual defrost, the sensor itself has failed.
The defrost sensor must be replaced. This is an internal repair behind the freezer's back panel.
-
Schedule a technician to replace the defrost sensor.
Provide your model number and the ER DM code. LG parts are widely available. The job typically takes 45–60 minutes.
When to Call a Professional
The ER DM error requires replacing the defrost sensor or its wiring harness. These are inside the freezer compartment behind the back panel. Contact LG support or a licensed appliance technician. Typical repair cost is $100–$200 including parts and labor.
Frequently Asked Questions
Will my LG refrigerator stop cooling with the ER DM error?
Not immediately — but over time, ice will build up on the evaporator coils if defrost cycles cannot complete. Eventually this blocks airflow and the fridge stops cooling. This can take days to weeks after the error first appears. Do not leave it too long.
Can I manually defrost my LG refrigerator to temporarily fix ER DM?
Yes — unplugging and letting the unit thaw completely can restore normal cooling for a while. This is a temporary fix only. The sensor still needs replacing to prevent the ice buildup from returning.
How much does it cost to fix an ER DM error on an LG refrigerator?
The defrost sensor part costs $15–$40. With technician labor, expect $100–$200 total. If the refrigerator is within LG's warranty period, contact LG at 1-800-243-0000 for a covered repair.