How to test whether the battery or controller is the reason of a non-starting scooter

Dear all, I am a new member of this forum.

Recently, I tried to use my old scooter x-treme x-500.
But it didn't start.
So I tried to do some trouble-shooting.

First of all, the batteries are really old. I am pretty sure I need to replace them.
But before I do that, I want to make sure the controller and motor are still good.

I used the multimeter to test the volt and electric current of the connector to the motor on the controller. (Power cord plugged in, twisted the handle).
I can hear a click from the motor, but the volt is 0, and a sudden current of 0.2A.

My question is will the motor run when the power cord is plugged in. Is the controller bad?

Thanks in advance.

First step would be to not make the same post twice in different threads


Did you measure the Battery voltage while twisting the throttle? Or each of the individual 12V blocks?
I imagine if the batteries are very old, the resistance could be so great that the Controller undervolt cutoff would engage because of the Voltage drop under even a slight load.

I suggest that you plug it in to the wall and try it like that. With or without the Batteries if possible.

Most controllers refuse to drive when charge power is applied. (To prevent accidentally driving off while charging)

Do the test on battery power only.

I guess that depends if the charge current goes through the Controller or directly to the Battery.