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Error code reference
Bosch Washer Error Code F21
Appliance starts delayed or start is delayed, typically caused by frequency fluctuations.
SourceBosch Washer WAE/WAT/WAW Series - Service Manualp. 22
Diagnostic procedure
The full F21 procedure
Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.
MyPros+ · DiagnosticsStep 1 preview
1
First diagnostic step
Advise customer; check that frequency is constant. Check plug and socket connections to the electronics module, unplug and replug, clean contacts where necessary.
SourceBosch Washer WAE/WAT/WAW Series - Service Manualp. 22
More steps, wiring diagram references, and verified part numbers
Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.
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Where this code is documented
1 manual in the MyPros+ library documents this code for Bosch washer.
Models covered by the manuals that document this code
75,000+ service documents · 20,000+ error codes · 100+ brands
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