> > > Not quite sure what you mean here. I had advice from a friend to bench test > the control module by providing 14V to the input of the 7812. On the good > PSU I can see the PWM operate, on the bad one the PWM is shutdown. >
And what happens if you feed in exactly 12 V on the output of the 7812? Would the PWM work then? By using a lab supply you could check if the circuit is sensitive to variation in the 12V supply. /Mattis > > Regards > > Rob > >
