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What this code means
Heater failure — no voltage detected at the heater relay (appears only in Diagnostic Test Mode).
First step from the service manual
Check that the wires are plugged in on the heater element and at the relay on the electronic control.
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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Related Whirlpool dryer error codes
1NTC fault (NTC R4)10No Wet Clothes17Filter LED flashes but filter is clean2NTC fault (NTC R2)3NTC fault (NTC R2)3 beepsThermistor or wiring harness is either short-circuited or open4Possible motor transistor error5Time error8Stuck Key81Lower Exhaust Probe Fault82Lower Axial Probe Fault83Lower Sail Switch Closed Fault84Lower Sail Switch Open Fault86Upper Exhaust Probe Fault87Upper Axial Probe Fault88Upper Sail Switch Closed Fault89Upper Sail Switch Open Fault90Upper Rotation Sensor Fault91Lower Rotation Sensor Fault92Gen 2 Card Reader Communication FaultafLow inlet air flow condition detected at installation (Amana models only).Blocked coin 1Blocked coin 1 or coin drop UI control circuit failure (coin recognition and…Blocked coin 2Blocked coin 2 or coin drop UI control circuit failure (coin recognition and…C2Coin 2 Failure.CCU communication errorCCU is not receiving communications from UI (display disabled while error…CLnOverheat warning due to reduced air flow, lint clog, or duct work not meeting…d1Dryer door sense error on CCU control board or due to power line interference…d12Lower dryer motor sense circuit error on control board or due to power line…d13Blocked coin 2 or coin drop UI control circuit failure (coin recognition and…D14Rotation Sensor Fault occurs when the control is in a cycle and does not detect…d16Not receiving communications from installed debit card reader in Enhanced…d17Lower dryer door sense error on control board or due to power line interference…D18Axial Probe Fault occurs when the axial thermistor reads a temperature out of…D19Exhaust Probe Fault occurs when the exhaust temperature transducer reads out of…d2Dryer motor control circuit errorD20Sail Switch Open Fault occurs when the sail switch does not close within 10…d21Lower motor sensed running when it should be off; check for line noise or…d22Upper motor sensed running when it should be off; check for line noise or…d23Upper button stuck switch (upper dryer cycle and upper dryer display disabled…d24Lower button stuck switch (lower dryer cycle and lower dryer display disabled…D3Lower Exhaust High Temp Faultd4Upper motor feedback circuit is sensing voltage with the door open or when the…D5Blocked Coin Dropd6Blocked coin 1 or coin drop UI control circuit failure; coin recognition and…d7Blocked coin 2 or coin drop UI control circuit failure; coin recognition and…d8Not receiving communications from installed debit card reader in Enhanced…d9Voltage detected below 90 VAC for 8 seconds.dCDoor Circuit FailureDebit card reader communication errorNot receiving communications from installed debit card reader in Enhanced…dFCCU errordOInvalid dryer door circuit stateE:01Overheating detected during drying due to clogged lint filter or exhaust vent…E:03Maximum heating time exceeded due to load too large or defective heater…E:11Overheating (fluffing) level 1E:12Overheating (fluffing) level 2E:13Maximum drying time exceededE:14No heat detected; heater not igniting (gas) or defective heater (electric).E:15Fault in heating circuitE:16Broken drive belt detected; faulty drive belt.E:17Door-NTC fault (TD)E:18Heater-NTC fault (TH)E:20Control fault 1E:21Invalid checksum due to incomplete update or defective PROM.E:22Control fault 2E:23Variant–Table Set Mismatch; invalid table set or variant.E:24Base software does not correspond to table set; invalid table set or variant.E:25Control fault 2E:26Control fault 2E1Top Radiant Sensor fault countE14Forward Rotation Sensor FaultE2Top Burner Ignitor fault countE3User interface keyswitch or software mismatch between control panel/touchpad…E4Bottom Radiant Sensor fault countE5Bottom Burner Ignitor fault countE6Bottom Exhaust High LimitE7Coin 1 Bad Coin countE8Coin 2 Bad Coin countE9Upper pocket forward rotation sensor fault countEAUpper pocket reverse rotation sensor fault countEBLower pocket forward rotation sensor fault count.ECLower pocket reverse rotation sensor fault count.EDS.A.F.E. DISABLEDExhaust thermistor openExhaust thermistor open, temperature drops below 18°F (>50 kΩ) for 1 minute in…Exhaust thermistor shortedExhaust thermistor shorted, temperature above 250°F (<500Ω) for 1 minute in Run…F-02Stuck button or user interface mismatch (keypad/user interface failure); only…F-20Heater #1 failure (Electric models only).F-21Heater #2 failure on dual element models (electric dryers only).F-24Inlet thermistor is openF-30Restricted airflow condition existsF-40Communication between the machine control and motor control is lost.F-41Blower motor failure.F-42Motor control detects a voltage less than 90 VAC (undervoltage failure).F-43Motor control detects a low voltage condition (undervoltage warning); dryer…F-44Motor control electronics failure.F-45Motor control electronics speed sensor failure.F-46Motor control detects an over-current or over-torque condition on the blower…F-50No voltage detected at the water valve relay (steam models only)F:01Primary control failure in the machine control electronics.F:02Stuck button or user interface mismatch; this fault code will ONLY appear when…F:22Exhaust thermistor circuit is open.F:23Exhaust thermistor has shorted.F:24Inlet thermistor is open; this fault code will ONLY appear when in the…F:25Inlet thermistor has shorted; this fault code will ONLY appear when in the…F:26Motor drive system failure.F:28Moisture sensor strip is open; this fault code will ONLY appear when in the…F:29Moisture sensor strip has shorted; this fault code will ONLY appear when in the…F:30Restricted airflow condition exists; this fault code will ONLY appear when in…f:31L2 line voltage errorF:40Communication between the machine control and motor control is lost.F:41Blower motor failure.F:42Motor control detects a voltage less than 90 VAC (undervoltage failure).F:43Motor control detects a low voltage condition (undervoltage warning); dryer…F:44Motor control electronics failure.F:45Motor control electronics speed sensor failure.F:46Motor control detects an over-current or over-torque condition (blower motor…f:50Water valve failureF:70No communication between the machine control and the console electronics.F:71No communication between the machine control and the console electronics.F:72Console electronics failure (F:72 through F:78).F:73Console electronics failure (F:72 through F:78).F:74Console electronics failure (F:72 through F:78).F:75Console electronics failure (F:72 through F:78).F:76Console electronics failure (F:72 through F:78).F:77Console electronics failure (F:72 through F:78).F:78Console electronics failure (F:72 through F:78).F0 E7Low Voltage ErrorF01Dryer motor control circuit error (cycles and price display disabled until…F03Blocked coin 2 or coin drop UI control circuit failure (coin recognition and…F04Not receiving communications from installed debit card reader in Enhanced…F05Dryer motor control circuit error (cycles and price display disabled until…F06Heater NTC (SET 2) value too high or too low (condenser dryer) / HX NTC value…F07Motor movement defect or broken drum belt.F1Dryer motor control circuit error (cycles and price display disabled until…F1 E7ACU Voltage Input Fault.F10MCU communication error (no communication between ACU and MCU).F11MCU motor failure.F12MCU not reset.F14Undervoltage condition.F15MCU failureF18MCU over temperature.F19MCU over voltage.F1E1No voltage detected at the heater, compressor, or motor relay, indicating a…F1E2Motor failure including over current, DC bus over/under voltage, locked rotor…F1E3Incorrect controller installed (electric models only); ACU and/or UI part…F1E5ACU parameter file missing; parameter memory invalid.F2UI Microprocessor is not able to read or verify EEPROM; cycles and price…F22Exhaust thermistor open, temperature drops below 18°F (>50 kΩ) for 1 minute in…F23Exhaust thermistor shorted, temperature above 250°F (<500 Ω) for 1 minute in…F25UI is not receiving communications from CCU (cycles and price display disabled…F26CCU is not receiving communications from UI (cycles and price display disabled…F28UI Microprocessor is not able to read or verify EEPROM (cycles and price…F29UI EEPROM memory is a CRC failure (cycles and price display disabled until…F2E1Indicates a stuck button (depressed for over 20 seconds) or UI mismatch; this…F2E2HMI DisconnectedF2E3User Interface and ACU model ID parameter mismatch caused by replacement of…F2E4UI software errorF2E5UI Software ErrorF3Blocked coin 2 or coin drop UI control circuit failure (coin recognition and…F3E1Indicates the exhaust thermistor is open or shorted; open if temperature drops…F3E2Indicates the moisture sensor strip is open or shorted; this fault code will…F3E3Inlet thermistor is open or shortedF3E4Compressor thermistor is open or shorted; open if temperature drops below 18°F…F3E5Indicates that the compressor and outlet thermistors are openF3E6Indicates the moisture sensor strip is openF3E7Indicates that the moisture sensor strip has shortedF3E8Indicates that the compressor sensor is openF3E9Indicates that the compressor sensor has shortedF4UI is not receiving communications from CCU (cycles and price display disabled…F4E1No voltage detected at the heater relayF4E2No voltage detected at heater relay 2 (electric models only), indicating a…F4E3Restricted/low air flow detected that may affect dryer performance.F4E4L2 line voltage error (electric models only); low L2 voltage (less than 50 V)…F4E5High limit exceeded; temperature threshold of the dryer has been exceeded…F4E7Indicates a problem in the supply voltage to the machine.F5Dryer motor control circuit error (cycles and price display disabled until…F5 E6Upper dryer door circuit error.F5E1Indicates a short in the Door Switch circuit.F6UI Microprocessor is not able to read or verify EEPROM (cycles and price…F6E1Communication error from UI to CCUF6E2Communication errorF6E3Communication errorF7UI Microprocessor is not able to read or verify EEPROM (cycles and price…F7 E6Lower Dryer Motor Circuit Error.F7 E7Upper dryer motor circuit error.F7 E8Lower Dryer Motor Sense Error.F7 E9Upper Dryer Motor Sense Error.F70UI is not receiving communications from CCU (cycles and price display disabled…F71CCU is not receiving communications from UI (cycles and price display disabled…F73UI Microprocessor is not able to read or verify EEPROM (cycles and price…F74UI EEPROM memory is a CRC failure (cycles and price display disabled until…F8UI EEPROM memory is a CRC failure (cycles and price display disabled until…F8E1No voltage is detected at the water valve relayF9E1Drain system errorF9E2Drain assembly failureFC E4USB FaultFC E5Software Update FailureFCE0Communication error between ECM and CCU (model WEL98 only).FCE1WIFI Module has not responded for a specified amount of time; communications…FCE2Wireless router cannot communicate with the internet (model WEL98 only).FCE3Antenna A (J2) is bad (model WEL98 only).FCE6Current Transformer B not functioning at J12 (model WEL98 only).FCE7Provisioning failureFEPower source frequency ErrorFP E1Coin 1 circuit error.FP E2Coin 2 Circuit Error.FP E3Card reader communication error.hEHeating ErrorL2Low or no line voltage detected (less than 50V) at installation.LdLower dryer door sense error on control board or due to power line interference…LFIndicates that the lint filter has been removed from running position.LoLow voltage detected.Low voltageVoltage detected below 90 VAC for 8 seconds.Motor control circuit errorDryer motor control circuit errorOEDoor open condition detected (displayed during diagnostic test mode when door…OFFMachine is out of service; displayed when service person manually takes machine…PFPower failuretSThermistor Short (display fault)UCUpper dryer motor control circuit error (upper dryer cycles and upper dryer…UFUpper dryer motor sense circuit error on control board or due to power line…UI communication errorUI is not receiving communications from CCU (display disabled while error…UI EEPROM CRC failureUI EEPROM memory is a CRC failure (display disabled until diagnostic code is…UI EEPROM read errorUI Microprocessor is not able to read or verify EEPROM (display disabled until…
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