Controller for MY1016Z3 24V 350W

I have successfully converted my bicycle into electric. I am using the MY1016Z3 24V 350W motor. I am using two automobile batteries, 12V 7AH connected in series to form 24 volt. After running for few hours, motor runs continuously without any input from throttle. The controller has gone defective?!!! or short circuited. Have I fried my controller because I am using unregulated current/voltage from the two lead acid batteries. Before frying up another controller, I want to know what should i do to prevent this. Please help!!!


Well-Known Member
In my opinion, the type of battery is not a cause for your problem.

Do the brake levers switch off the motor when this happens? Hope so.

rich c

Well-Known Member
Successfully converted? What capacity is the controller? If 10 amps, you may have fried it with those batteries in series. Are you using a throttle? PAS?

This is the controller that I have used. It says a under voltage protection of 20V and current limit feature of 33A.

But I doubt these features.

I am using a throttle to adjust the speed of the motor.

I am using two of the batteries mentioned above and I connect them in series to form 24 v. Do I need some voltage/current regulation circuit before i feed the controller with amps from those batteries. Please help me to sort out before i fry another controller.
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Well-Known Member
You had a 24 V controller. You had 24 volts. You're OK. It doesn't matter if you had 100 24 V batteries in parallel or the two 12V batteries in series. You're not overloading the controller. It determines what it needs in current and if operating correctly, there's no problem.

If it were me, I'd make sure the throttle is working OK and that it didn't malfunction,

Does the motor still run uncontrolled when you power up the old controller? Does it shut off when you squeeze a brakelever. If you hooked them up, your brake levers have switches that shut off the moto.

If it does start up on its own, does disconnecting the throttle shut off the motor? If it does, you can suspect your throttle, and do further tests. If not, your controller blew up. Replace it.
I disconnected the throttle from the motor controller. Then connected the battery and the motor with the motor controller. Then the motor started spinning immediately at high speed without any intervention or connection from the throttle.

Does it have to be with shorted FET/MOSFET (Field Effect Transistor) inside the controller. Its going to be nightmare job for me searching for these transistors around and then soldering them into the circuit board.

I am not using any brake lever to be connected into the controller.

Did the two batteries threw too many amps into the controller that the circuit could not withstand, but short those FETs. It says it comes with a undervoltage protection of 20v and a current limit feature of 33A.

If that is not enough, do I need to design my own current limit circuit with transistor, resistor and capacitors. Should I buy one online. I need some advice from experienced people who have faced this problem. Please help me!!!


Well-Known Member
My guess is that there are a million or more scooters in China using this motor/controller and most of the owners are happy. There's no incentive to design a more robust unit because it wouldn't sell, Meanwhile, all the little shops over there copies everyone else, often without understanding the design. So maybe you got copy of a copy. Or the importer bought a pallet of lower quality units.

In addition, while I think this is an inexpensice controller at $5.27 USD if I were in China, with the different exchange rates in India, this may not be cheap to you. Good luck when it arrives and I think it will work.