Starting System: Description and Operation
OperationWhen the Ignition Switch is moved to the "START" position, voltage is supplied to the Starter Solenoid through the Starter Enable Relay contacts and, either the Transmission Position Switch (Automatic Transmission) when in "PARK" or "NEUTRAL," or the Clutch Start Switch (Manual Transmission). The PASS-Key II Decoder Module energizes the Starter Enable Relay by grounding one side of the Relay Coil only when the Theft Deterrent System has not been activated.
When the Starter Enable Relay is energized, the normally open contacts close, completing the circuit to the Starter Solenoid. When the Starter Solenoid circuit is completed, both the Hold-In and Pull-In Windings are energized. The circuit through the Pull-In Winding is completed to ground through the Starter Motor. The windings work together magnetically to pull in and hold in the Plunger. The Plunger moves the Shift Lever. This action causes the Drive Assembly to rotate as it engages the Flywheel ring gear on the Engine. At the same time, the Plunger also closes the solenoid switch contacts in the Starter Solenoid. Full battery voltage is then applied directly to the Starter Motor and it cranks the Engine.
As soon as the Solenoid Switch contacts close, voltage is no longer applied to the Pull-In Winding since battery voltage is applied to both ends of the windings. The Hold-In Winding remains energized and its magnetic field is strong enough to hold the Plunger, the Shift Lever and the Drive Assembly Solenoid Switch contacts in place to continue cranking the Engine.
When the Ignition Switch is released from the "START" position, battery voltage is removed from the PPL wire and the junction of the two windings. Voltage is applied through the motor contacts to both windings to ground at the end of the Hold-In Windings. However, the direction of current flow through the Pull-In Winding is now opposite the direction of the current flow when the winding was first energized. The magnetic fields of the Pull-In and Hold-In Windings now oppose one another. This action of the windings, with the help of the Return Spring, causes the Drive Assembly to disengage and the Solenoid Switch contacts to open simultaneously. As soon as the contacts open, the starter circuit is turned "OFF."