Ford Mustang Service Manual: Pinpoint Tests

Inspection and Verification

WARNING: When servicing starter motor or carrying out other underhood work in the vicinity of the starter motor, be aware that the heavy gauge battery input lead at the starter solenoid is "electrically hot" at all times. A protective cap or boot is provided over this terminal that must be installed after servicing. Be sure to disconnect the battery negative cable before servicing the starter. Failure to follow these instructions may result in personal injury.

WARNING: When working in area of the starter motor, be careful to avoid touching hot exhaust components. Failure to follow these instructions may result in personal injury.

WARNING: When using a remote starter switch or jumper wire, be sure the ignition switch is in the OFF position and the transmission is in PARK (A/T) or Neutral (M/T) with the parking brake control fully applied.

1. Verify the customers concern by operating the starting system to duplicate the conditions.

2. Inspect to determine if any of the following mechanical or electrical concerns apply.

Visual Inspection Chart

Mechanical

Electrical

  • Starter motor

  • Brackets

  • Battery
  • Battery junction box (BJB) fuse ignition switch (40A)
  • Central junction box (CJB) Fuse 6 (20A)
  • Fuse 24 (10A)
  • Damaged wiring harness
  • Starter Relay
  • Loose or corroded connections

3. If the inspection reveals an obvious concern that can be readily identified, repair as necessary.

4. If the concern remains after the inspection, determine the symptom. GO to Symptom Chart .

Symptom Chart

Condition Possible Sources Action
  • The engine does not crank and the relay does click
  • Battery.
  • Fuse.
  • Starter motor/solenoid.
  • Ignition switch.
  • Circuit.
  • Go To Pinpoint Test A .
  • The engine does not crank and the relay does not click
  • Fuse.
  • Battery.
  • Starter relay.
  • Ignition switch.
  • Digital transmission range (TR) sensor.
  • Starter solenoid.
  • Clutch pedal position (CPP) switch.
  • Circuit.
  • Go To Pinpoint Test B .
  • The engine cranks slowly
  • Battery.
  • Starter motor/solenoid.
  • Circuit.
  • Go To Pinpoint Test C .
  • Unusual starter noise
  • Starter motor mounting.
  • Starter motor.
  • Incorrect starter drive engagement.
  • Go To Pinpoint Test D .
  • The starter spins but the engine does not crank
  • Starter Motor
  • Damaged flywheel/ring gear teeth.
  • INSPECT the starter motor mounting and engagement.

    REPAIR as necessary

  • INSPECT the flywheel/ring gear for damaged, missing or worn teeth. REPAIR as necessary.
    Inspection and Verification
    Inspection and Verification WARNING: When servicing starter motor or carrying out other underhood work in the vicinity of the starter motor, be aware that the heavy gauge battery input lead at the s ...

    Component Tests
    Inspection and Verification WARNING: When servicing starter motor or carrying out other underhood work in the vicinity of the starter motor, be aware that the heavy gauge battery input lead at the s ...

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