Bosch Washer Error Code F21: Meaning and Fix
Reading the washer display
On a washer the code appears on the digital display or as a pattern of flashing cycle lights. Note it exactly, including any dashes or sub-codes, then unplug the washer for five minutes and run a short drain cycle to see whether it returns. Bosch shows the code with a leading E and a number on both dishwashers and washers.
Bosch (part of BSH Home Appliances) uses E-numbered codes on dishwashers and washers. Its dishwashers share control platforms with Thermador and Gaggenau, so the same fault can appear on those brands. The codes apply to model numbers such as SHPM65Z55N, SHE53T55UC and WAT28400UC; check the label on your unit to confirm yours.
What causes F21
- A worn motor, brushes or bearings that stall under load
- A failed motor control module, triac or tachometer/Hall sensor feedback
- A loose or damaged wire harness between the motor and the control board
- Carbon brushes worn on a universal motor
How to fix it
- Power the machine down and unplug it, then clear the drum, spray arm or impeller by hand to make sure nothing is binding.
- Check that the load is not oversized or unbalanced and that the drive belt or coupling, if fitted, is intact.
- Check brush length where applicable and look for black dust inside the motor housing.
- Inspect the motor harness and connectors for damage and reseat them firmly.
- Measure the motor windings and tachometer sensor against your service data; look for open or shorted readings.
- Replace the motor or its control board depending on which part fails the test, then run a test cycle.
Parts you may need
| Part | Part no. | Buy |
|---|---|---|
| Washer Drum Drive Motor | 00142197 | Find part |
Part numbers are OEM references; confirm fit by your model number before ordering. Some links are affiliate links; we may earn a commission at no extra cost to you.
Questions
What does error F21 mean on a Bosch washer?
The drive motor is not delivering expected speed. Exact behavior can vary by model and software version; confirm against your own manual.
Can I keep using my washer while F21 is showing?
No. Repeated attempts to start a stalled motor can overheat it or damage the control board.
How do I clear F21, and can I fix it myself?
Cancel the program, switch the appliance off and leave it unplugged (or the breaker off) for about five minutes, then restart. The code only stays cleared if the underlying problem is fixed, so work through the steps above. Parts here involve electronics, heating or sealed components, so consider a qualified technician if the basic checks do not clear it.
Other Bosch washer codes
Sources
Part numbers are OEM references; confirm fit by your model number before ordering. Meanings compiled from manufacturer and parts-retailer documentation; see sources below. Unplug the appliance before opening it.
Applies to models including WAT28400UC, WAT28402UC, WAW285H1UC, WAP24200UC.