HEY,
I COULD BE WRONG BUT IT LOOKS LIKE '1 COIN 1 PLAY' IS THE DEFAULT POSITION.BEING IT IS THE ONLY SWITCH THAT DIRECTLY CONNECTS TO COIL ' S '.
BOTH OTHER ALTERNATIVES GO THRU SWITCHES X , AS , S WHICH PERHAPS ENGAGE PULSES FROM THE MOTOR . LIKE MOST THINGS PROBABLY NEED TO LOOK AT A BIT MORE OF THE CIRCUIT .