Electrolux Dryer Error Code E66 — Heater Relay Stuck Closed
What this means
The E66 error code on Electrolux dryers indicates the control board has detected that the heater relay is stuck closed — meaning the heating element continues to receive power even when the control board is trying to turn it off. This is a dangerous condition that can cause overheating. The dryer will shut down immediately as a safety measure. The primary cause is a welded relay contact on the control board, sometimes triggered by a previously shorted heating element.
Alternate codes: E 66
Step-by-step fix
4 stepsDisconnect power immediately
Turn off the dryer's circuit breaker. A stuck-closed heater relay is a fire hazard — do not attempt to use the dryer until this is resolved.
This is a safety-critical code. Do not ignore it or try to use the dryer.
Test the heating element for shorts
Before replacing the control board, test the heating element for a short to ground. A shorted element may have caused the relay to weld shut. The element should show resistance (10–50 ohms between terminals) but OL to the housing.
If the element is shorted, replace it before installing a new board — otherwise the new board's relay will also weld.
Inspect the control board
Access the main control board and inspect the heater relay area for burn marks, discoloration, or a visibly damaged relay. The relay is typically the largest component on the board near the heavy-gauge heater wires.
A welded relay may look physically intact from the outside but is fused shut internally.
Replace the control board
Replace the main control board. The welded relay cannot be repaired — the entire board must be swapped. Install the new board, reconnect all wires, and run a test cycle.
After repair, also clean the dryer vent — restricted airflow contributes to overheating that stresses the relay.
When to call a professional
This is a safety-critical repair. If you are not comfortable diagnosing electrical components, call a professional immediately.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
Learn more about our sourcesParts you may need
Heating Element
Part #137234600 · $40–$80
If element is shorted to ground (replace before new board)
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