Electrolux Dryer H4 / B4 Error Code — What It Means
The H4 code on an Electrolux dryer indicates a stuck key error. The control board thinks one of the console buttons is being held down or is electrically stuck. This can happen when a physical button is jammed, the user interface membrane has failed, or the control board is in a glitched state. Note that EH4 or ExH4 on some Electrolux compact or heat-pump models may indicate an electrical supply voltage fault instead, not a keypad problem, so verify your exact model number and the displayed code before ordering parts. Because Electrolux code meanings vary by platform, confirm which code you actually see on the display.
Common Causes
- Physically stuck or damaged button A console button is jammed, binding, or physically broken so the control thinks it is always pressed.
- Faulty user interface or membrane panel The button panel membrane or circuit has failed, sending a continuous input signal to the board.
- Control board glitch or corrupted state The main control has locked up and thinks a key is stuck even when no button is pressed.
- Wiring or connector fault in keypad circuit Loose, corroded, or damaged wiring between the user interface and control board can mimic a stuck-key signal.
- Supply voltage issue on EH4/ExH4 variants On models where the code displays as EH4 or ExH4, the fault may indicate that incoming voltage does not match the dryer’s rated supply.
Step-by-Step Fix
- Disconnect power at the breaker or unplug the dryer and wait two minutes to perform a hard reset, then restore power and check whether the code clears.
- Attempt the factory reset procedure by holding the Temperature and Dryness buttons together for about six seconds, then release and see if the control resets.
- Inspect the console buttons physically by pressing lightly around each key to see if one is stuck down, binding, or damaged.
- Check the user interface wiring by removing the top or front panel and verifying that the connector between the button panel and the control board is fully seated and not damaged.
- Replace the user interface or button panel assembly if the code persists and you have confirmed a stuck or failed keypad, following your model’s disassembly instructions.
- Verify supply voltage on EH4/ExH4 codes by confirming that the wall receptacle or hard-wired supply matches the voltage and phase rating on the dryer data plate.
- Replace the main control board if the code remains after a new user interface has been installed and all wiring and voltage checks are normal.
Parts Often Needed
| Part | Notes |
|---|---|
| User interface control board / button panel assembly | Amazon | Primary replacement for persistent H4 stuck-key faults. Match by exact model number. |
| Main electronic control board | Amazon | Replace if H4 persists after keypad replacement or if EH4/ExH4 voltage fault is confirmed and board is damaged. |
| Wiring harness or connector kit | Amazon | Repair or replace if console or control board connectors are visibly damaged or corroded. |
When to Call a Pro
Call a qualified appliance technician if the code does not clear after a power reset and you are uncomfortable removing panels or working around live voltage. If you have replaced the user interface panel and the fault persists, or if your model displays EH4/ExH4 and you are not confident testing supply voltage safely, professional diagnosis of the control board and electrical supply is the safest next step. Always verify your exact model number before ordering parts, because Electrolux code definitions vary widely across platforms.