Check the bU0 setting to see if it is set to the proper battery voltage, 48V. Also try doing a few charge/discharge cycles to condition the battery.
That bU0 setting (step 6) isn’t there. The manual says it should be there. It skips 6 and goes to psd.
1. Cr = Clear temporary data (trip reset)
Select “y” to clear the temporary data (average speed, max speed, current speed, single trip, time).
2. S7 = Speed KM / Miles. Switch speed mode to kilometer or mile.
3. bL1 = Backlight brightness (1 - 5)
4. OFF = Auto off LCD screen (1 - 15) minutes
The LCD screen switches OFF automatically when not in use. Select from 1 to 15 minutes.
5. Wd = Wheel diameter (20, 26, 27.5) (20F, 26F specific for 4” fat tires)
The wheel diameter must be set according to the tire size. Wrong tire size will cause inaccuracy in the speed readout.
6. bU0 = Power voltage (default 48V) (do not change)
7. PSd = Advance settings
Enter the password 1919 to access the advance settings mode.
8. SPL = Speed limit (default 32 km / 20 miles)
Set the maximum speed limit.
9. SAs = Pedal assist sensor responsiveness (default 2) (do not change)
Enables you to speed or delay the pedal sensor response when pedalling.
10. Sdr = Motor responsiveness (default 2)
Enables you to adjust motor responsiveness from gradual to instance. 0 - 3 (gradual to quick response).
11. PAs = Pedal assist levels (default 1-7)
Enables you to change the number of power assist levels between (1-3, 1-5, 1-7, 1-9).
12. EnP = Battery percentage indicator (0 disabled, 1 enabled)
13. Hd6 = Cruise control (0 disabled, 1 enabled)
To start the cruise control, push and hold the throttle at the desired speed for 8 seconds.
14. Sdd = Taillight flashing mode (0 disabled, 1 enabled)
15. dPd = LCD secure lock feature (0 disabled, 1 enabled) (default password 0000)
This feature will lock the LCD screen and will require a password to unlock and use the electrical system.
16. PPd = Set password for LCD secure lock