Error Code 21
The battery is not supplying the required voltage to power the
display and motor. Use the display to view the real-time voltage
being output from the battery. It can also be checked using a
multimeter. If the battery is old and has been charged /
discharged many times, it may need to be replaced.
Error Code 22
When you press and release the throttle, it should return to the
original position. Remove any obstructions. Check the throttle
and throttle cable for damage, such as a cut or frayed cable.
Error Code 23
Motor Phase Abnormality
Check the cable that connects the rear hub motor to the rest of
the system and make sure it is free from grit or contaminants and
is firmly connected. This error might appear if you don’t reconnect
the cable after removing the rear wheel (for example, after
changing a flat tire, or transporting your bike in the trunk of a car).
At least one of the motor wires has been damaged or is
Error Code 24
Motor Hall Signal Abnormality
Check the motor cable connection point by the chainstay, and
where the motor cable connects to the internal controller. The
wire might be disconnected or damaged, reconnect the motor
cable. Another possibility: Damage to the motor cable as it exits
the axle, perhaps if the wheel was dropped on the cable.
Error Code 25
Disconnect electronic brake shut offs. Likely a magnet sensor
issue. This can happen often after a crash or when the bike is
dropped. See video on Ride1UP YouTube channel, or under
instructional videos on the support page to resolve.
Error Code 30
A problem with the connection from the internal controller to the
display. The display is not receiving vital information.
Source: This is all straight out of the Ride1UP LMT’D gen2 manual, I've uploaded a copy of the manual here: