Motor controller error — drum motor speed controller malfunction detected
The F21 error on the Bosch WAJ24060IN indicates motor controller error — drum motor speed controller malfunction detected. This typically occurs due to motor control board or triac failure. A qualified technician can usually diagnose this in 15–25 min, but the steps below will help you understand the issue.
Safety Warning
This is a high-severity error. Unplug the appliance immediately and assess the situation before attempting any repair.
Safety Warning
This repair is recommended for certified technicians only. The diagnostic steps below can help you understand the issue before calling for service.
Common Causes of F21
- 1Motor control board or triac failure
- 2Drum motor winding fault causing incorrect speed response
- 3Wiring fault between motor controller and drum motor
- 4Motor overloaded by excessive laundry weight repeatedly
How to Fix F21
- 1
Step 1
Disconnect the washer from power immediately
- 2
Step 2
Reduce the load size by removing half the laundry — overloading is a common stress cause
- 3
Step 3
Spin the drum slowly by hand to check for binding or grinding
- 4
Step 4
Unplug the washer for 10 minutes to reset the motor controller
- 5
Step 5
Plug in and run a light load to test — if the error clears, overloading was the trigger
- 6
Step 6
If the error returns with a reduced load, a technician must diagnose the motor controller circuit
Tools Needed
When to Call a Technician
Error returns with a reduced load and drum spins freely — the motor controller module needs professional diagnosis
Frequently Asked Questions
Common questions about Bosch F21 error
F21 points to a problem with the motor speed controller — the circuit that controls how fast the drum spins during wash and spin. Repeated overloading stresses this module over time, but the error can also come from a standalone electronic failure. If reducing your load size does not clear F21, the controller board needs professional diagnosis.
No — the F21 error typically stops the washer from completing cycles, as the drum may not spin correctly. Continuing to operate the washer with a faulty motor controller can cause further damage to the motor. Stop using the washer and arrange for a technician to diagnose the controller before restarting.
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