How to Fix Bosch Washer Error F21

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⚠️ Safety Warning: Appliance repair involves electricity, gas, and moving parts. Always disconnect power before working on any appliance.

Error Code: F21 Difficulty: Hard

Problem: Uneven drum rotation, engine problems, or a faulty tacho generator.

⚖️ Repair Decision

⚠️ CHECK WARRANTY / AGE

$100 – $250 Range

How to Fix F21 Error (Step-by-Step)

Unplug the washer from the power source and confirm the error stays cleared during a full test cycle.
Remove the back panel to get access to the motor.
Locate the carbon brushes on the motor. They are spring-loaded and make contact with the commutator.
Disconnect the electrical wires attached to the brushes and remove the screws holding them in place.
Slide the old brushes out and insert the new ones, making sure they are oriented correctly.
Secure the new brushes with the screws and reattach the electrical wires.
Replace the back panel, plug in the washer, and run a spin cycle to test the motor.
Turn the appliance off, wait about 2 minutes, then turn it back on.

OEM Part #: Motor Carbon Brush

Estimated Market Price: $40-$415

Verified Compatible Alternatives:

Still Not Working?
If the replacement part didn’t fix the issue, you may have a wiring problem or main board failure.

Appliance Type

Appliance Age

Estimated repair cost (parts, or parts + labor) Most DIY parts are $50–$250. If you have a quote, use the total.

Is it under warranty?

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