Starter motor: Operation

When the correct ignition key is put in the ignition, the transponder sends a code to TWICE which grounds the starting relay actuating coil.

When the ignition is turned to the start position, the starting relay is activated and the operating circuit to solenoid terminal 50 closes. The solenoid engages the pinion with the ring gear on the engine flywheel and closes a switch so that the starter motor commutator is supplied with power via the slip brushes from terminal 30.

Once the engine has started and the engine speed has exceeded the starter motor rpm, the pinion is disengaged from its shaft via a free wheel, preventing the starter motor from overrevving. Releasing the ignition key breaks the starting circuit and the operating circuit to the solenoid, whereby a spring returns the pinion to its rest position.