Starting System: Description and Operation
STARTING SYSTEMThe starting system is designed to start the vehicle's engine. The system consists of a starter motor with a solenoid, a transaxle mounted park/neutral switch (automatic transaxle) or clutch pedal actuated switch (manual transaxle), a crank contact in the ignition switch, and associated wiring. The battery supplies current to the starter motor to crank the engine during starting.
OPERATION
With the ignition switch in START and the transaxle in P (Park) or N (Neutral), current flows to terminal S of the cranking motor solenoid. Current through the pull-in winding also flows through the cranking motor. The motor turns slowly at first so the gears mesh and the solenoid contacts close. This allows full battery current to flow directly to the cranking motor. With full battery voltage at the M terminal, the cranking motor armature rotates and cranks the engine.
When the ignition switch is released from the START position, current to the S terminal is cut off. Current from the battery continues to flow to the cranking motor through the pull-in and hold-in windings. The current through the windings flows in opposite directions so it creates opposing magnetic fields. The fields cancel each other, releasing the driver mechanism. The shift lever returns to its at-rest position and the starter solenoid contacts open, cutting off current to the starter motor.
DESCRIPTION OF STARTER
The starters use a planetary gear drive between the armature and motor pinion. The gear drive allows the use of permanent magnets eliminating heat that normally would be produced by coil fields and simplifies motor construction since there are no internal field coils and connections. In addition, when compared to a conventional field coil motor with the same cranking power, the permanent magnet gear reduction motor is only about half as large in size and weighs about half as much.