Bafang · Speed sensor
Bafang error code 21
Wheel speed isn’t being measured
What you can check
Check the spoke magnet is in place, facing the sensor 10–20 mm away, and the sensor plug is in. If it stays, your dealer needs to look at it.
Dealer if the fault comes back
Trolda cannot read Bafang motors yet. The code list is here to help you anyway.
Sources
Explained in Trolda's own words from the manufacturer's public documentation. Trolda is not affiliated with the manufacturer. If in doubt, ask your dealer.
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