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What this code means
Ductwork is approximately 90% blocked (displayed for 2 hours only).
First step from the service manual
Check the duct condition; inspect exhaust system for restrictions and damage; clean or repair ductwork.
Next steps: diagnose the root cause
1
Verify the error code is active
Power cycle the unit and see if the code returns. If it does, the fault is persistent and requires diagnosis.
2
Get the full diagnostic procedure
Get step-by-step guidance, test values, and wiring diagrams from the OEM service manual.
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What’s available for LG dryer models
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Related LG dryer error codes
1 FlashAir in gas line, flame sensor coated with aluminum oxide, or incorrect gas…25Wire connection is wrong or wire connection is loose (power supply issue).2EElectronic control problem (over voltage error).3CMotor Relay short problem.3EMalfunction detected in the motor relay circuit.4 FlashesInternal failure of the ignition control module.5 FlashesLoose or disconnected wiring, or open igniter/igniter sensing circuit/voltage…5EOverflow detected three times in succession or drain pump does not work.6 FlashesInoperative gas valve, inoperative flame sensor, or loose/disconnected wiring.7 FlashesIncorrect wiring, incorrect polarity, loose/disconnected wiring, or flame…9C1Electronic control problem (Invalid Voltage).ACElectronic control problem (Invalid Communication).AddWater supply issueAdd waterSteam generator sensors do not detect that the steam generator is full within…AECompressor errorAE3A communication error between the DR Modem and the MAIN PBA.AE4A communication error between the WIFI PBA and the MAIN PBA.AE5A communication error between the LCD PBA and the MAIN PBA.bC2Incorrect button state.bEInvalid dry time in excess of expected dry time; sensor bar open or excessive…bE2Invalid state of key circuit short for 30 seconds (button stuck/pressed…C1Unit is detecting items inside the drum or there is an error on the dry sensor…C8About 80% of the vent is clogged (Smart Install vent blockage test result).C80About 80% of the vent is clogged (Smart Install vent blockage test result).C9Over 90% of the vent is clogged (Smart Install vent blockage test result).C90Over 90% of the vent is clogged (Smart Install vent blockage test result).CdDisconnection of card reader wire.CE1Compressor out temperature exceeds 115°C; compressor shuts off and re-operates…CFDisconnection of card reader wire.Constant LightInternal failure of the ignition control module.CtThe internal temperature of the dryer is too low or too high during vent…d-Display PGM error or display programming mode indicator.d75Ductwork is approximately 75% blocked (displayed for 2 hours only).d80Exhaust system is partially blocked or restricted (approximately 80% blockage)…d95Ductwork is approximately 90-95% blocked (displayed for 2 hours only).dCThe dryer is running with the door open.dEDoor open errordFInvalid state of door sensor circuit; loose or open wire terminals at the door…dHDisplayed when thermistor temperature has increased about 17 degrees for 10…dORunning the dryer with the door open (invalid state for more than 0.25 seconds).dSDisplayed when thermistor is opened or shorted.dtInvalid dry time in excess of allowed dry time.EWater supply pump errorE13Poor drainage pump failure or blockage of the drainage line.E21Ignition controller lockoutE24Air flow switch did not turn ONE5Water supply pump errorE7Drum outlet thermistor connector out of line, poor contact, or thermistor…EESensors do not detect that steam generator is full within 60 seconds, or wire…ELEELB (Earth Leakage Breaker) sensor error indicating irregular current or…Empty WaterPump malfunction or water reservoir full, signaling that the condensate water…EtCheck the heater thermistor; for gas models, check that gas is supplied…F0Display/LED code shown during diagnostic test for models DLE5977W/B and…F1Display/LED code shown during diagnostic test for models DLE3777W and DLG3788W…FCInvalid power source frequency.FEInvalid power frequency; not using regular power source frequency or invalid…gASGas supply or service turned off (gas model only).HCInvalid heating temperature in running the dryer.hEInvalid heating temperature during dryer operation, indicating a heating issue.HSDisplayed when the thermistor temperature has increased about 17 degrees for 10…L06Diagnostic/service code for Electric Type dryer model.L07Diagnostic/service code for Gas Type dryer model.LEThe motor is bound (motor binding/locked rotor condition).LE1Restricted motorLE2Low electric current detectedLE3Heater thermistor open/short (Drum in)LE4Low temperature thermistor open/short (Evaporator In)LqC1Displayed when power is turned on for first time without connecting card reader…nCNFC module is open or shorted (displayed in test mode only).nEWi-Fi modem (module) single product error.nFWi-Fi product is not registered (normal for unregistered products).nPElectric dryer power cord is not connected correctly, or house power supply is…nUNFC module is wrong/faulty (displayed in test mode only).odInvalid state of key circuit short for 75 seconds; display PCB key circuit is…OEDrainage pump malfunctionPFElectric dryer power cord is not connected correctly, or house power supply is…PSElectric dryer power cord is not connected correctly, or house power supply is…Rapid FlashingIncorrect power supply frequency.SEError displayed during diagnostic test when an abnormal condition is detected…tCThe thermistor1 resistance is very low or high.tC5The thermistor2 resistance is very low or high.tEInvalid heating temperature detected, possibly due to clogged lint screen or…tE (steam generator)Steam generator thermistor is open or shorted.tE (wire connection)Wire connection (Black/White/Red) is wrong or loose.tE1Thermistor errortE2Thermistor errortE3The resistance of the thermistor for the vent blockage detection operation is…tE4Steam generator thermistor is open or shorted (displayed only in test mode).tE5Water supply pump failuretE6Compressor out thermistor open or shorted.tE7Evaporator in thermistor open or shorted.tOClogged lint screen or vent is restricted (related to temperature out-of-range…tSClogged lint screen or vent is restricted, causing abnormal temperature sensor…tS2Compressor discharge pipe thermistor temperature open or short circuit.U-Main PGM error or main programming mode indicator.
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