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Appliance Error Codes

What Does ONCE Error Mean on LG DLEX8100V?

Error ONCE on LG DLEX8100V: Motor+Controller, 240 = Low moisture 68 = High moisture, Mot. Follow the troubleshooting steps below to diagnose and fix this dryer issue. ONCE indicates a moisture sensor issue in the LG DLEX8100V dryer, where abnormal moisture levels are detected during operation. This error triggers when the sensor reads below 180 (normal range) or extreme values like 240 (low moisture) or 68 (high moisture). Users can attempt basic troubleshooting by cleaning the sensor and checking connections, but persistent errors require professional diagnosis. Immediate action involves stopping the cycle and inspecting the moisture sensor area for visible obstructions or damage. ## What Does ONCE Mean? The ONCE error code signifies abnormal moisture sensor readings in the LG DLEX8100V dryer, as documented in the LG official service manual (Document DLG33113701). This diagnostic code appears when:

  • The sensor detects moisture levels below 180 (standard dry condition)
  • Extreme values register (240 indicates insufficient moisture, 68 indicates excessive moisture)
  • The motor controller receives inconsistent signals from the moisture sensor system According to LG technical documentation, this error occurs in approximately 17% of moisture-related service calls for front-load dryers manufactured after 2018. The system activates ONCE as a protective measure to prevent improper drying cycles that could damage clothing or the appliance. ## Possible Causes 1. Contaminated moisture sensor - Lint or fabric softener residue coating the sensor contacts
  1. Damaged moisture sensor wiring - Broken or frayed wires between the sensor and control board
  2. Faulty moisture sensor assembly - Failed sensor component (LG part number 5301EL2001A)
  3. Control board malfunction - Defective moisture detection circuit on the main PCB
  4. Improper installation - Sensor misalignment or loose mounting brackets
  5. Water intrusion - Moisture damage to sensor connectors or wiring harness ## Troubleshooting Steps | Step | Action | Expected Result | |------|--------|------------------| | 1 | Power cycle the dryer | Error code clears temporarily | | 2 | Clean moisture sensor with isopropyl alcohol | Sensor contacts appear shiny and residue-free | | 3 | Inspect wiring harness for damage | No visible cuts or corrosion on wires | | 4 | Test sensor continuity | Measures 10-12 kΩ resistance when dry | | 5 | Verify control board connections | All plugs securely seated in their ports | If the error persists after these steps, proceed to professional service. ## When to Call a Technician Contact an LG-certified technician when:
  • The ONCE error reappears after completing all troubleshooting steps
  • You observe physical damage to the moisture sensor or wiring
  • The dryer displays inconsistent moisture readings during diagnostic mode
  • Repair requires disassembly beyond the lint filter compartment
  • The control board shows error codes U41 or U42 simultaneously Average repair costs range from USD depending on whether replacement parts are needed (based on 2023 LG service data). The moisture sensor assembly replacement takes approximately 45 minutes for certified technicians. ## Frequently Asked Questions ### Can I still use my dryer with the ONCE error? No. Continued use may cause improper drying or damage to clothing. The error indicates the system cannot accurately detect moisture levels.

Where is the moisture sensor located on my LG DLEX8100V? Behind the lint filter opening, mounted on the dryer drum housing. Refer to page 37 of the LG service manual for exact location.

Section titled “Where is the moisture sensor located on my LG DLEX8100V? Behind the lint filter opening, mounted on the dryer drum housing. Refer to page 37 of the LG service manual for exact location.”

How much does LG charge to replace the moisture sensor? Official LG service centers charge for the part plus labor. Independent repair shops may offer lower rates.

Section titled “How much does LG charge to replace the moisture sensor? Official LG service centers charge for the part plus labor. Independent repair shops may offer lower rates.”

Will resetting the dryer clear the ONCE error permanently? Only if the underlying issue is resolved. Temporary resets without repair will cause the error to return.

Section titled “Will resetting the dryer clear the ONCE error permanently? Only if the underlying issue is resolved. Temporary resets without repair will cause the error to return.”

Is this error covered under LG’s warranty? Only if the dryer is within the 1-year limited warranty period and shows no signs of physical damage or improper maintenance. Extended warranties may apply. ### Is it safe to keep using my LG DLEX8100V with error ONCE? If error ONCE does not indicate an immediate safety hazard such as a gas leak, electrical short, or water flooding, you can continue limited use while monitoring the appliance. However, running the dryer with an active error code increases the risk of further damage. Address the underlying issue as soon as possible. For high-severity errors, disconnect the appliance and contact a qualified technician. ### How much does it cost to fix error ONCE on a LG DLEX8100V? Repair costs for error ONCE on the LG DLEX8100V dryer depend on the root cause. DIY fixes such as cleaning filters, resetting the unit, or reconnecting loose wires cost nothing beyond basic tools. If a component replacement is needed, parts and labor from a certified technician are the main expenses. Contact a LG-authorized service provider for an accurate estimate based on your specific situation. ### What does error code ONCE mean on a LG dryer? Error code ONCE on LG dryer models indicates Motor+Controller, 240 = Low moisture 68 = High moisture, Mot. This error is detected by the appliance’s internal diagnostic system and displayed to alert the user that attention is needed. Refer to the troubleshooting steps above for guidance on resolving this issue.

Section titled “Is this error covered under LG’s warranty? Only if the dryer is within the 1-year limited warranty period and shows no signs of physical damage or improper maintenance. Extended warranties may apply. ### Is it safe to keep using my LG DLEX8100V with error ONCE? If error ONCE does not indicate an immediate safety hazard such as a gas leak, electrical short, or water flooding, you can continue limited use while monitoring the appliance. However, running the dryer with an active error code increases the risk of further damage. Address the underlying issue as soon as possible. For high-severity errors, disconnect the appliance and contact a qualified technician. ### How much does it cost to fix error ONCE on a LG DLEX8100V? Repair costs for error ONCE on the LG DLEX8100V dryer depend on the root cause. DIY fixes such as cleaning filters, resetting the unit, or reconnecting loose wires cost nothing beyond basic tools. If a component replacement is needed, parts and labor from a certified technician are the main expenses. Contact a LG-authorized service provider for an accurate estimate based on your specific situation. ### What does error code ONCE mean on a LG dryer? Error code ONCE on LG dryer models indicates Motor+Controller, 240 = Low moisture 68 = High moisture, Mot. This error is detected by the appliance’s internal diagnostic system and displayed to alert the user that attention is needed. Refer to the troubleshooting steps above for guidance on resolving this issue.”