Nothing turns on, so power isn't reaching the display. Most likely cause: a flat battery, a battery switch that's off, or a battery that isn't clicked in. Try this first: charge the battery.
When nothing turns on at all, the cause is almost always somewhere between the battery and the display: an empty battery, a battery switch that's off, a battery that isn't clicked in, or an unplugged connector. Batteries can also put themselves to sleep after being fully drained or stored for a long time. Plugging in the charger often wakes them up.
Step-by-step checklist
Work from the top. Steps go from free and easy to shop jobs. Switch the bike off before touching any connector. Tick each step as you go. Your progress is saved on this device.
Parts you might need
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Only buy a part if the free steps didn't fix it. Always match the voltage and connector type to your bike.
Digital multimeter
Checks whether wires are broken and measures voltage.
Link coming soon
Replacement e-bike charger
Only if your charger is faulty. Must match your battery's voltage and plug type exactly.
Link coming soon
Electrical contact cleaner spray
Cleans dirt and corrosion from connector pins and battery contacts.
Link coming soon
Replacement e-bike battery
Only if a shop confirms your battery is worn out or faulty. Must match voltage, mount and connector.
When it's time for a shop: if you've worked through every step and the problem is still there, take the bike to an e-bike shop. Bring your notes on when it happens, plus the code and your error history.