You really have me confused now. You say it runs, but now you saying it causes sparks and high current?
I am going to restate you can turn off speed control and lock the engine in one direction. That would cause what you describe in your first post. You just need to unlock it and turn speed control back on.
As far as the lock on light, that could also be a part of all this. It runs full speed because it has full track voltage all the time.
You need to either send it to a tech, or go return it and get another type. Frankly if you get a PS-2 version you will be real happy with sounds, performance. G
