Kickscooter ES4 brake issue (Not headlight/fuse issue)
 

Hello, I have an ES4 kickscooter and was coming home from work yesterday down a large hill and applied the brake. The electric brake started to slow the scooter and then it felt like it let go and I had to use the fender brake only. When I started to ride the front wheel shuttered and made a loud grinding noise. I stopped and reset the scooter thinking the electric brake stuck or something. It still vibrates horrible when riding and goes very slow. When I let off the throttle it rolls fine. This tells me the electric brake is stuck. Any ideas on how to reset or calibrate the brake?

This forum is about useless in the fact that there is nobody here to answer questions so I'll answer my own.

If you apply the brake whole going fast down a hill it can fry the controller boards braking module. I purchased a new controller after weeks of trial and error and it is fixed.

How to Fix
 

Same exact issue happened to me -- would have been helpful to know that we're not supposed to use the electric brake on hills...

How did you purchase the new controller, and who installed it for you?

Thank you so much for posting by the way!

That happened to me too guys about 2 weeks ago going down a hill. A large bang then grinding noise and no power. It was the second time taking it back after the back foot brake actually snapped in half. I’ve also had the front steering mechanism come loose regularly and was continuously tightening screws. I took the scooter back and they advised the factory had forgotten to include the internal loctite screws & they must have had a “bad batch” as others had been brought back with similar issues.
Doesn’t exactly inspire confidence. Anyway they wanted to replace the front braking system & other issues and I said replace the whole scooter is cursed and obviously one of the bad batches. Waiting on it to be delivered.
Lesson = don’t use front brake going down steep hills, perhaps I shouldn’t ride it at the max 35km’s with 2nd battery, lastly - be careful riding on uneven footpaths as it’s clearly not designed for anything else than smooth roads...

reply
 

Same happened to me about a month ago .
The battery also started to draining very fast and the battery takes a longer time to charge even after full power .

Please help me with the problem.

Always full throttle, use regen braking on max, lean back knowing it does break with force just letting up on the throttle. If you need more breaks than that, step or jump off. You’ll be fine, also plan ahead like your going fast enough to die, cause you just might be.

Same thing happened here. I stepped on the rear brake going through an intersection and now it makes a horrible noise like the brake is stuck on. It was the first day I owned the scooter. Anyway to fix this?

You guys that are saying it makes a horrible noise, are you getting error code 18? I've been getting this error, and it makes the ES4 completely unrideable. Got the scooter May 3rd, it's only been 12 days. Any suggestions? Segway Technical support has not replied.

@hogoscooter

I’m in the same boat as you- recently purchased an ES4 and error 18. Only had it for a few days before it error showed up. Once in a while the error will away when I turned it on but it inevitably comes back. The control board located in the tube right below the battery is shot. I’ve been desperately trying to reach Ninebot technical support to no avail. The support web form does nothing, email goes unresponsive, and the their tech support number goes straight to voicemail. I’ve had the scooter for almost two months and have only been able to use it for two days. Called a local Segway dealer by me and they refused to service it since replacement parts from Segway are non-existent. I ended up ordering a control board on eBay and doing the work myself. I’m also trying to get a claim through my credit card for defective product. I really regret this purchase and even more so for buying online from the Segway webstore.

This isn’t an easy swap and it will take some patience but hope this helps anyone else in the same boat. Do a search on YouTube for disassembly videos, good luck!

Most probably the control board has fried.
I have had two control boards die although I haven't had error 18.
Two of the mosfets which control one of the motor phases goes open circuit.
I have tried swapping the mosfets from one board to the other but that doesn't work at all.

Your best bet is to replace the control board and use the regenerative braking at conservatively as possible.

This is obviously a design flaw. My M365 with no back brake brakes awesomely going down steep hills.