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Shimano STEPS error E020: Battery to drive unit communication error
Shimano STEPS (all drive units, shown on SC-E5000/E6100/E7000/E8000 displays and via EW-EN100 LED)Fix at homeRide with caution
E020 means the drive unit and the battery are not talking to each other properly. The battery may show charge but the motor refuses to assist, or assist cuts out on bumps. Nine times out of ten this is a contact or cable issue, not a dead battery.
Likely causes
- Battery not fully seated or latched
- Dirty, corroded or bent contacts on the battery mount
- Damaged wiring between battery mount and drive unit (integrated frames route it inside the down tube)
- Water in the battery connector after washing or heavy rain
- Battery BMS fault
How to fix Shimano STEPS error E020
- Switch off, remove the battery, clean the contacts on battery and mount with a dry cloth or contact cleaner, refit and latch it firmly
- Inspect the mount for loose screws or a mount that has shifted in the frame
- With the battery out, look for damaged wiring at the mount connector
- Switch on and test; if E020 persists, try another known-good battery if you have access to one
- If it stays, the dealer needs to check the battery mount wiring and battery communication in E-TUBE
Go to a dealer if: See a dealer when cleaning and reseating the battery does not help; E-TUBE identifies whether the battery, the mount wiring or the drive unit port has failed.
Warranty: Battery and mount faults are covered under warranty; corrosion from washing with a pressure washer is usually not.
Typical cost: Cleaning is free; a new battery mount or cable is moderate; a battery is the expensive outcome.
Warranty: Battery and mount faults are covered under warranty; corrosion from washing with a pressure washer is usually not.
Typical cost: Cleaning is free; a new battery mount or cable is moderate; a battery is the expensive outcome.
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 E020 myself?
Yes: remove, clean, refit the battery and power-cycle. That fixes most E020 cases.
Can I keep riding with E020?
Riding without assist is fine, but a battery that keeps dropping communication may also cut out mid-ride.
Is E020 covered by warranty?
Usually yes if the cause is a faulty battery or mount rather than corrosion or damage.
Related Shimano STEPS codes
E021 · Battery not compatible with the systemE022 · Battery communication faultE023 · Battery abnormality detected
Not an official Shimano STEPS document. Compiled from workshop experience and public service information; details can differ per system version and bike brand.