You may search for a long time to get circuit schematics (plans) for the electronic controls and still never find them.
You may do well to find an electoniocs technician and ask him to invetsigate - the control circuitry will be quite simple.
If the motor runs continuously then it has no control - it may be a very simple fault such as a failed motor drive transistor - a cheap and easy replacement - 20 mins $5.
Pay the technician well - the older ones are usually better because of more experience.
Good luck...
Peccavi
January 2010
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