On Wed, 27 Jun 2012 08:33:49 -0700 (PDT), "Denis G."
wrote:

On Jun 27, 6:01Â*am, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:
"Denis G." fired this volley in news:054f7966-
:

Diagnostics on pg 74 (F-8) indicate that it might be a problem with
the speed sensor (fault).

It's not a PDS cart, so it has no speed sensor.

This controller is a "dumb" PWM type, without regenerative braking or
automatic speed controls.

LLoyd

So no circuit feedback.

Oh well, it always pays to check the simple things first. Maybe the
board won't be too complicated if you have to figure it from scratch.
I understand the basics of PWM, but don't have practical experience.
I would now guess a bad SCR or the oscillator circuit went kerflooey,
but I'm mostly a hex head.
No SCRs any more - better than 90% are MosFet units - I suspect one
side of the unit, either high or low, is bad, but that's just a guess.
If one side is shorted the control would go into current limit.