Section 03-06: Starting System
1996 F-Series and Bronco Workshop Manual
DESCRIPTION AND OPERATION

Sequence of Operation

  1. On an automatic transmission-equipped vehicle, shift lever is positioned in PARK (P) or NEUTRAL (N) to close neutral switch. On a manual transmission-equipped vehicle, clutch pedal is pressed to close clutch pedal position switch (CPP) (11A152).

  1. Key is turned to START position.

  1. Battery voltage is connected to starter relay coil through ignition switch (11572). Current flow through relay coil generates magnetic field.

  1. Iron core is drawn into relay coil core. Disc connected to core closes electrical contacts inside relay.

  1. Electrical contacts and disc complete circuit between relay battery feed terminal and starter solenoid S terminal.

  1. Starter solenoid is energized, creating a magnetic field in solenoid pull-in and hold-in windings.

  1. Iron plunger core is drawn into solenoid coil.

  1. Lever connected to drive assembly engages drive pinion gear with flywheel ring gear.

  1. When iron plunger core is all the way into the coil, its contact disc closes circuit between battery and motor terminals. As current flows to starter motor, solenoid pull-in coil is bypassed. Hold-in coil keeps drive pinion gear engaged with flywheel.

  1. Current flow through field coils generates magnetic field.

  1. Current flow through brushes and armature wires generates magnetic field. Repelling magnetic fields cause armature to rotate.

  1. The gear remains engaged until key is released from START position.

  1. An overrunning clutch in the drive assembly protects the starter motor from excessive speeds during the brief period before the key is released from the START position (as the engine (6007) starts).

    Starter System Sequence of Operation

    ItemPart NumberDescription
    1—Key Start
    2—Neutral Safety Switch
    3—Starter Relay
    4—Starter Relay Contact and Plunger Assembly
    5—Starter Solenoid S Terminal
    6—Starter Solenoid Hold-In and Pull-In Windings
    7—Starter Solenoid Plunger
    8—Shift Lever Drive Pinion and Flywheel Ring Gear
    9—Starter Solenoid Contact Disc
    10—Starter Motor Field Coils
    11—Starter Motor Armature
    12—Overrunning Clutch