I think muduckase has hit the nail on the head.
My question is specific to the A300-600.
So the blowers will close (stop operating) when i select crank. I did assume this based on the cockpit sound significantly reducing when crank is selected with no bleed air (ie no APU/external bleed).
So prolonged use of crank with no bleed air will damage the avionics due to lack of ventilation. Makes sense.
So can someone just confirm what closes and what open with crank selected with no bleed pressure?
I assume the starter motor will not arm due to it being mechanically activated by bleed pressure and not an electrical signal from the starter switch (it must have both the switch in the right position and bleed pressure going to the starter motor).