I think the first thing you have to do is establish if the speed controller is working.
I would connect a lamp accross the output of the speed controller after disconnecting from the motor and then wind the voltage up and down to see if the lamp reacts.
If it doesn't then you have to either fix the speed controller or replace it.
In the event that it is fine then the electric motor is at fault and it would be my guess a brush is not touching the commy.
Hope this helps,
Regards,
Doug |