The F21 error code on a Bosch washing machine indicates a problem with the drum not spinning, often caused by motor, Hall sensor, or drain issues.

Meaning of F21 Error

The F21 error occurs when the washing machine drum cannot rotate. The machine attempts to self-correct, but if the drum fails to spin after several attempts, the F21 code appears on the display washingcodes.com+1. This can be triggered by:

• Motor issues: Worn motor brushes, motor failure, or electrical faults in the motor circuit washingcodes.com+1.
• Hall sensor failure: The rotor position sensor may not send speed data to the control board, stopping the drum washingcodes.com.
• Drain problems: Blocked drain pump filter or kinked drain hose can prevent proper water flow, affecting the spin cycle homegeargeek.com.
• Foreign objects: Items stuck in the drum can physically block rotation washingcodes.com.
• Electrical issues: Voltage spikes or control board faults may also trigger the error JustAnswer.

Troubleshooting Steps

1. Power Reset: Turn off and unplug the machine for a few minutes, then plug it back in and restart nationalappliancerepair.co.uk+1.
2. Check Drum: Manually spin the drum to detect obstructions or unusual sounds washingcodes.com.
3. Inspect Drain: Clean the drain pump filter and ensure the drain hose is free of kinks or blockages homegeargeek.com.
4. Door Lock: Ensure the door is properly closed and latched nationalappliancerepair.co.uk.
5. Motor and Hall Sensor: If comfortable with DIY, remove the rear panel and check motor brushes or the Hall sensor. Replace if worn or faulty washingcodes.com+1.

Reset Procedure

To reset the F21 error:

1. Unplug the machine for 30 minutes.
2. Press and hold the Start button while turning the dial to the Off position until the display shows “0” and lights flash homegeargeek.com.
3. Alternatively, for some models, turn the program knob to specific positions while pressing the spin button to clear the code JustAnswer.

When to Call a Professional

If the above steps do not resolve the issue, or if there is evidence of tank leakage, persistent clicking, or motor/control board faults, contact a qualified appliance repair engineer. F21 can indicate serious mechanical or electrical problems that require professional intervention washingcodes.com+1.

Preventive Tips

• Regularly clean the drain pump filter and check the drain hose.
• Avoid overloading the drum.
• Remove small objects from pockets before washing.
• Schedule periodic maintenance to inspect motor brushes and electrical connections.
  Following these steps can help identify the cause of the F21 error and determine whether a DIY fix is possible or professional repair is needed.