Loonitick
Supercharged
My guess is when there is not enough juice to roll the engine over, there would most likely still be enough to operate the seat latch solenoid.
When mine was left on (with high beam lights) for two hours and would NOT move the engine at all, it still would sweep and operate the horn.
Again, just my limited 'lectrical thoughts . . .
Bit of a difference deliver 5 amps for ECU and lights and 150+ to the starter