Yamaha PW error E20: Speed sensor signal abnormal
Yamaha PW series (PW-X3, PW-X2, PW-X, PW-ST, PW-TE, PW-SE, PW-CE) and Giant/Liv SyncDriveFix at homeRide with caution
E20 is shown when the speed sensor produces a signal but it is implausible, for example too many pulses per rotation, a flickering signal from a loose magnet, or a tuning device manipulating it. Assist may be capped or cut. Also shown on Giant/Liv (SyncDrive) bikes, sometimes with a leading zero (E01) or as 'Er' followed by the number on older Yamaha displays.
Likely causes
- Magnet loose and wobbling past the sensor
- Two magnets fitted or a spare magnet left on the wheel
- Speed tuning device
- Sensor cable intermittent
How to fix Yamaha PW error E20
- Check there is exactly one magnet, firmly fixed, passing the sensor cleanly
- Remove any tuning device
- Reconnect the sensor cable
- If E20 stays, dealer sensor test
Go to a dealer if: Dealer with the Yamaha/Giant diagnostic tool (Yamaha PW diagnostic or Giant's RideControl/e-bike diagnostic software) is needed to read the fault log and test the component when the home checks do not clear the code.
Warranty: Component faults inside the drive unit, battery or display are covered by the bike brand's warranty via the dealer; damage from crashes, water ingress or tuning devices is not.
Typical cost: Usually free / DIY.
Warranty: Component faults inside the drive unit, battery or display are covered by the bike brand's warranty via the dealer; damage from crashes, water ingress or tuning devices is not.
Typical cost: Usually free / DIY.
Still stuck? Take a photo of the display and show it to a local e-bike workshop. Bring the bike's system name (e.g. Bosch Performance Line CX) and the exact code; that saves diagnostic time and money.
Frequently asked
Can I reset E20 myself?
Yes, once the magnet/sensor setup is corrected and the bike power-cycled.
Can I keep riding with E20?
Yes, safe to ride with reduced assist.
Is E20 covered by warranty?
Not if a tuning device was the cause.
Related Yamaha PW codes
Not an official Yamaha PW document. Compiled from workshop experience and public service information; details can differ per system version and bike brand.