Ninebot Max Error Code 24
"System Voltage detection is abnormal, Please check the Control Board"
This error is thrown when the ESC detects an abnormal battery voltage.
Most often this occurs when the user performs an upgrade from the standard voltage of 36v to 48v.
In some cases, it may be that the battery has become overcharged as well.
This is a separate error from the low voltage warning Ninebot Max Error Code 45 warning that the battery has been "Overly discharged".
If the abnormal voltage is intended (such as is the case when performing the aforementioned battery mod to 48v), flashing Custom Ninebot Max/G30 Firmware with an error suppression level of 2 (ignore battery mod warnings) should solve it.
If the error is unexpected and the user has not performed any modifications, the battery may need to be run down and recharged.
Leave the scooter on for a while and attempt to run the battery percentage down by using power i.e. turning the headlight on, trying to ride it, etc...
If the voltage runs down and the error goes away, keep using the scooter until it is near 25% and then charge it fully again.