1: Use a multimeter to measure whether the output voltage of the charger is consistent with the marked voltage. If there is no voltage or voltage is too low, it means the charger is faulty. Replace it
2: If the charger is fine, but the battery still won’t charge, It may be that there is a problem with the connection of the charging port. Open the cover to check whether the connection between the charging port and the battery is normal. If the wire falls off, weld it tightly with an electric iron.
3: Check whether the battery fuse is short-circuited. If the fuse is short-circuited, replace the fuse.
4: If the red light and green light flash alternately and there is a rattling sound, stop charging the vehicle immediately. Open the cover and unplug the cable connecting the battery to the controller port, and charge the battery separately. If it is charged normally at this time, indicating that it is a controller problem, just replace the controller. If the cable connected between the battery and the controller is unplugged, the red and green lights of the charger are still flashing, which may be a short circuit of the battery BMS, just replace the battery
5: Battery shows fully charged very quickly or can go very short distance. The battery is probably faulty after ruling out the two situations.
1: The display voltage parameter is set incorrectly
2: The charger has an issue