LG Refrigerator Error Code rS

LG Refrigerator Error Code: rS — What It Means

The LG error code “rS” typically indicates a problem with a refrigerator temperature sensor, often referred to as the refrigerator or room sensor. When the control board detects an out-of-range reading, an open circuit, or a short circuit on the sensor circuit it logs the rS error and may stop normal temperature control. This can lead to incorrect cooling cycles, longer run times, erratic temperatures, or even the compressor running constantly. Common user impacts include food spoilage from warm temperatures, excessive frost buildup if defrost cycles are affected, higher electricity bills, frequent cycling or noise, and potential secondary faults if left unaddressed.

Common Causes

• Faulty refrigerator temperature sensor (NTC thermistor) giving incorrect or no reading
• Damaged or corroded wiring harness or connectors between the sensor and main control board
• Loose or disconnected connector at the sensor or the PCB
• Moisture or ice intrusion into the sensor area causing intermittent shorts
• Failure on the main control board (PCB) that misinterprets sensor signals
• Recent power surge or outage that caused a transient fault in electronics
• Physical damage to the sensor from impact or repairs
• Issues with nearby components (evaporator fan or defrost system) that change actual temperatures and trigger the sensor alarm

Troubleshooting Steps

1. Safety first: unplug the refrigerator or switch off the circuit breaker before inspecting any internal parts.
2. Power cycle the unit: wait 60 seconds after unplugging then plug back in to see if the code clears. Sometimes transient faults reset on a reboot.
3. Locate the refrigerator temperature sensor: consult the service manual or user manual for sensor location. Typically it is positioned inside the fresh-food compartment or behind a plastic cover near the evaporator.
4. Visually inspect the sensor and harness: look for corrosion, disconnected plugs, damaged insulation, or signs of water/ice ingress. Reseat any connectors firmly.
5. Check wiring continuity: with the appliance unplugged, use a multimeter to check continuity from the sensor connector to the control board connector and inspect for open circuits or shorts to ground.
6. Test the sensor resistance: measure the thermistor resistance at a known temperature and compare with the specification in the service guide. If resistance is open, shorted, or out of spec, replace the sensor.
7. Inspect related components: verify evaporator fan operation and defrost components; a failed fan or blocked airflow can create abnormal readings that trigger the rS code.
8. Swap / replace sensor if available: if you have a known-good sensor or OEM replacement, swap it in to confirm the code clears and normal operation resumes.
9. Check for ice build-up: excessive frost on evaporator coils can affect sensors; perform manual defrost if required and investigate defrost system operation.
10. Reset and monitor: after repairs or replacements, restore power and monitor temperatures and cycles for 24–48 hours to confirm resolution.
11. If the rS code persists after replacing the sensor and verifying wiring, the main control board may be faulty and require professional diagnosis or replacement.

Maintenance / Prevention Tips

• Keep door gaskets clean and sealing properly to prevent moisture and warm air intrusion.
• Avoid overpacking the refrigerator so air can circulate and sensors read accurately.
• Clean condenser coils regularly to reduce compressor strain and temperature fluctuations.
• Keep the refrigerator level to ensure doors close correctly and sensors are not stressed by vibrations.
• Inspect connectors and wiring during routine cleaning or maintenance for early signs of wear or corrosion.
• Perform an occasional manual defrost if you notice frost build-up in the freezer compartment.
• Install a surge protector on the refrigerator circuit to protect electronics from power surges.
• Avoid placing hot or warm items directly against internal walls where sensors are mounted.
• If you live in a high-humidity area, check for condensation inside the cabinet that could reach sensors.
• Follow the manufacturer recommended service intervals and keep the service manual handy for troubleshooting guidance.
• Address minor refrigerant or airflow issues promptly before they cause sensor anomalies.
• Use genuine OEM replacement sensors and parts to ensure correct specifications and reliability.
• When cleaning interior panels near sensors, unplug the unit first to avoid accidental damage to components.

FAQs

Conclusion / Safety Notice

Working on refrigeration systems involves electrical components and, in some cases, refrigerant-containing assemblies. Always unplug the refrigerator before performing inspections or repairs, use insulated tools, and follow the manufacturer service manual. If you need to access the control board, compressor, or cooling system components, consider professional service to avoid injury or damage to the appliance.

If you are comfortable with basic diagnostics (visual checks, reseating connectors, and simple part replacement), you can attempt those first. For persistent rS errors, ambiguous wiring issues, or control board replacement, contact an authorized LG technician or a certified appliance repair professional to ensure a safe, reliable repair.