⚠️ Safety Warning: Appliance repair involves electricity, gas, and moving parts. Always disconnect power before working on any appliance.
Error Code: F40 Difficulty: Hard
Problem: Communication error between the machine control and motor control.
How to Fix F40 Error (Step-by-Step)
- UNPLUG THE DRYER. Turn off the corresponding circuit breaker for complete safety before beginning any work.
- Remove the top panel of the dryer by unscrewing the screws at the back or sides, then sliding the panel off. This will give you access to the main control board.
- Locate the main control board (power module), typically housed in a plastic case near the front of the dryer, and the motor control board, usually located at the bottom of the dryer near the motor.
- Carefully inspect the wiring harness that runs between these two boards. Look for any signs of damage, such as pinched, broken, or burnt wires. Ensure the connectors at both ends are securely plugged in.
- Disconnect and then firmly reconnect the main wiring harness plugs on both the main control board and the motor control board. Sometimes a loose connection is all that’s wrong.
- If the connections are secure and undamaged, the main control board (power module) has likely failed and needs to be replaced. Carefully label and disconnect all wire harnesses from the old board, remove its mounting screws, and install the new board in its place.
- Reconnect all wiring harnesses to the new control board, reassemble the dryer by securing the top panel, and plug the dryer back in to test its operation.
- Turn the appliance off, wait about 2 minutes, then turn it back on.
Parts Availability Note: For this Electrolux/Frigidaire error code, exact OEM part numbers can vary by model revision and serial range. We’ve listed the most likely component(s), but confirm compatibility using your full model number before ordering. If no exact SKU is shown, use this guide for diagnosis first, then verify the matching OEM part on RepairClinic or PartSelect.
Still Not Working?
If the replacement part didn’t fix the issue, you may have a wiring problem or main board failure.
Most DIY parts are $50–$250. If you have a quote, use the total.
More options (for a better recommendation)
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Expert: Mike Sullivan
EPA Section 608 Certified Technician with 18+ years experience.
Read Editorial Standards →Browse all Bosch error codes: Bosch Error Codes
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