Bosch Washing Machine F21 Error - Drum or Motor Fault

What does this error code mean?

Symptoms users may notice

1. The drum may fail to turn or may struggle during wash or spin.
2. The programme may stop before spin completes.
3. The washer may retry drum movement and then show F21.
4. There may be unusual motor noise, but any burning smell should be treated as a stop-and-call-engineer warning.

What users often notice

1. Users often notice Bosch F21 when the machine reaches a movement or spin stage and the drum cannot rotate normally, or when the drum will not turn properly at all.

Why is this happening?

1. Motor drive or motor speed monitoring issue
2. Worn motor carbon brushes on some Bosch models
3. Drive circuit or wiring issue that needs diagnosis
4. Drum movement blocked by an overloaded load or trapped item
5. Control reading that cannot confirm normal drum movement

What this usually points to

How to fix this safely

1. Stop the cycle, switch the washing machine off, and unplug it from the mains.
2. Check whether the drum is overloaded and remove some laundry if the load is heavy or tightly packed.
3. Look for clothing caught around the door seal or drum lip if it is clearly visible and can be removed safely.
4. Restore power and test one short spin or rinse cycle only if the drum area is clear and there is no burning smell or electrical concern.
5. Stop using the machine and call an engineer if F21 returns, the drum struggles to move, or you would need to remove panels.

You can safely reduce an overloaded drum and remove a clearly visible trapped item around the door seal. Returning Bosch F21 usually needs engineer diagnosis because the motor drive and control circuit are not user-service checks.

Safety boundary: Stop if there is a burning smell, electrical concern, harsh grinding noise, repeated cycle failure, or any need to remove panels.

What not to do

1. Do not keep retrying spin cycles if the drum is struggling to move.
2. Do not remove panels, test the motor, or inspect wiring yourself.
3. Do not ignore burning smells, harsh grinding noises, or repeated cycle failure.

Common misdiagnoses

1. F21 can be mistaken for a drainage or fill fault because the cycle stops, but the main concern is usually drum movement or motor drive.
2. Bosch F21 is different from Bosch E29 and Bosch E30, which are water-related faults.

Reset steps

1. Restore power only after checking for overload or a clearly visible trapped item.
2. Run one short spin or rinse cycle if the drum can move freely and there is no unusual smell or noise.
3. Stop if F21 returns, the drum still struggles to turn, or the machine fails the test cycle.

Intermittent vs persistent faults

Useful hub links

Related motor drive fault codes

Relevant guide

Frequently asked questions