This may not be of any help, but it may also be :P
You seem to say that if you set the start PWM of the cooling fans to, say 50PWM, the fan(s) don't turn?
If that is the case, what happens if you manually give them a 'nudge', just to help them get going... do they continue to spin afterwards?
You seem to say that if you set the start PWM of the cooling fans to, say 50PWM, the fan(s) don't turn?
If that is the case, what happens if you manually give them a 'nudge', just to help them get going... do they continue to spin afterwards?