Backlight brightness and sleep timer on an S866 / S830 / S861

P01 sets the backlight 1–3 (some firmware 1–5); P04 sets how many minutes of no riding before the display switches itself off.

Step by step

1. Switch the display on. Press and hold + and − (up and down) together for about 2–3 seconds. On most bikes a password screen appears: enter 1919 (set each digit with + / −, confirm with power). If 1919 is refused, try 0512, 0000 or 8018. The parameter list then opens at P01.
2. P01 is the first item: set 1 (dim) to 3 (bright) with + / −.
3. Press power to P04: 0 = never auto-off, 1–60 = minutes. 10 is sensible; 0 will flatten the battery if you forget the bike on.
4. Power (short press) moves to the next parameter; + / − change the value; hold + and − together to save and exit.
5. On the riding screen hold + for 2 seconds to toggle the light and night backlight.

Can't find it?

Screen always dim: light toggle on (hold +). Display turns off mid-ride: P04 too low is not the cause (it needs zero speed); look at the battery connector or P15 low-voltage instead.

Frequently asked

Other S866 / S830 / S861 LCD (generic hub-motor e-bikes, Fiido, Engwe, Himiway etc.) guides