Controller 46604A

[ltbeer]

the controller only runs at full speed when turned on. It no longer changes the speed. Is there any repair that can be done?

[richiy]

Possibly the controller shaft is broken in the full speed position.
I see four holes in the bottom of the case where you will find the fasteners. Since the newer packs are low voltage, you should be able to open it up and check it out.

richiy

[ltbeer]

I checked the controller knob like you suggested and looked at it with the back opened but there is no way to tell if the shaft is broken. However, the knob is probably not working correctly.  I think my grandson was changing the direction switch without turning it off first. Anyway, I am bidding on a used controller on E Bay. thanks for your response, Rich.

[richiy]

Probably that is best. They are cheap enough.
I suspect some kind of potentiometer, but I have never seen the inside of this particular controller.
I do remember seeing a power pack a few years ago and I think the potentiometer was a piece of copper PC board that was etched and a wiper on a shaft.

richiy

[ltbeer]

Yes. It's the same controller.

[ltbeer]

Bought a Bachmann used controller model 46005a on EBay for $17.50 and it works perfectly. Problem solved. Thanks for your advice JBrock and Richly.