I have seen in some videos that the 109 was started by manually hand cranking the engine, instead of a Kaufman starter or electric motor and battery system.
On antique automobiles, the hand crank would directly roll the crankshaft, but the 109 propeller did not turn at all until after several crank revolutions by hand.
Also I heard a siren-like whine during the cranking. I presume the crank either turned an electric starter generator or some kind of inertia wheel, but I just don't know and I'm lousy at research.
Can someone describe or diagram the Bf-109 engine staring system?