E4 Error on Hiboy S2 series

In plain English

The scooter cut power because the current went above its safe limit. Heavy loads and steep hills can trigger it, but a code that stays can mean a wiring or controller fault.

Work from the top. Steps go from free and easy to shop jobs. Switch the scooter off before touching any connector. Tick each step as you go. Your progress is saved on this device.

1. 1Switch off and restartFree Turn the scooter off, wait 30 seconds, then turn it back on. If the code clears, note what you were doing when it appeared, in case it comes back.
2. 2Check the wheels turn freelyFree With the scooter switched off, spin each wheel by hand. Look for a rubbing brake, something caught in the wheel, or a soft tire that makes the motor work harder.
3. 3Write down the code and when it happensFree Take a photo of the display and note when the code appears: at switch-on, when you set off, on hills, in rain or while charging. Support will ask for this.
4. 4Contact support or a service centerShop job If the code stays after these checks, stop riding and contact the brand's customer support or an authorized service center. Don't open the deck, battery, controller or motor: most scooter batteries and controllers aren't user-serviceable.