S866 Display Error Codes & Problems
Small black-and-white LCD with a separate button pad. Very common on hub-motor conversion kits and budget e-bikes.
About the S866
- Codes show as E plus two digits (like E07) in the multi-function area, where ODO and TRIP normally appear. source
- Codes clear by themselves once the problem is fixed and the bike reaches about 6 km/h with motor help. source
- No official S866 manual could be found online, so these meanings come from a typed-out copy of the manual's table. Some S866 units show codes that aren't in it (E30 has been reported, linked to a loose connector). If yours does, use the Not sure pages. source
2 Pick the code on your screen
S866 code list, commonly reported. 13 codes.
- E01Reserved (not a listed fault)
- E02Brake signal
- E03Pedal-assist sensor fault
- E04Walk (push) assist is on
- E05Cruise mode is on
- E06Battery voltage too low
- E07Motor fault
- E08Throttle fault
- E09Controller fault
- E10Communication error (receiving)
- E11Communication error (sending)
- E12Battery (BMS) communication error
- E13Headlight fault
No code? Pick your problem
- No powerDisplay won't turn on
- Cuts out on hillsLoses power climbing
- Throttle not workingPedal assist works, throttle doesn't
- Pedal assist not workingMotor doesn't help when pedaling
- Battery not chargingCharger light or battery won't charge
- Speed shows 0Speedometer wrong or stuck at 0
- Motor stutters or jerksJerky, grinding or juddering motor
- Battery dies fastRange has dropped