LG Refrigerator Error Code Er dS — Defrost Sensor Error
What this means
The Er dS error code indicates the defrost sensor (thermistor) on the evaporator is not sending the correct temperature reading. This sensor tells the control board when the evaporator is warm enough to end the defrost cycle. If it fails, the defrost cycle may run too long (wasting energy) or not at all (causing frost buildup).
Alternate codes: dS
Step-by-step fix
3 stepsAccess the defrost sensor
Remove the food from the freezer. Unscrew and remove the rear panel inside the freezer to expose the evaporator coils. The defrost sensor is a small component clipped to the evaporator, usually near the top of the coils.
Test the defrost sensor
Disconnect the sensor's wire connector. Measure the resistance with a multimeter. At freezer temperature (approximately 0°F / -18°C), the sensor should read approximately 16,000–17,000 ohms. At room temperature, it should be approximately 5,000 ohms. A reading of 0 or infinity indicates failure.
If you're testing at room temperature after removing the panel, wait a few minutes for the sensor to warm up before taking your reading.
Replace the defrost sensor
Unclip the faulty sensor from the evaporator. Install the replacement in the same position. Reconnect the wiring, reassemble the evaporator panel, and restore power.
Make sure the sensor is making good thermal contact with the evaporator tubing for accurate readings.
When to call a professional
If the defrost sensor tests normally but the error persists, the main control board's defrost circuit may be faulty. A technician can test the board outputs during a defrost cycle.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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