GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1999 🢒 Silhouette Ext. 🢒 Engine 🢒 Engine Electrical 🢒 Starter No Load Test
  1. Remove the starter motor from the vehicle. Refer to Starter Motor Replacement .
  2. Secure the starter motor in a vise or suitable test stand.
  3. Turn the carbon pile off and open the switch.

    4. Caution: Keep fingers, tools, and any other objects away from the opening in the drive end housing while making electrical connections. The strong shifting action of the starter solenoid can cause severe personal injury or damage to components as the drive pinion moves into the cranking position.


    Object Number: 1052 Size: SH
  4. Connect a voltmeter from the starter motor terminal to the starter motor frame (ground), as shown.
  5. Connect the starter motor and an ammeter in series, from the positive terminal of a fully charged 12 V battery.
  6. Connect a switch from the S terminal of the starter solenoid to the starter motor terminal.

    7. Notice: Never operate the starter motor for more than 30 seconds at a time. Allow it to cool for at least two minutes. Overheating, caused by too much cranking, will damage the starter motor.

  7. Close the switch.
  8. Adjust the carbon pile load to obtain 10 V on the voltmeter.
  9. Record the following readings:
    10. • The armature speed (RPM)
    • The current draw (ammeter)
  10. Turn the carbon pile OFF and open the switch.
  11. Compare the measurements with the specifications. Refer to Starter Motor Usage .

The test results indicate the following conditions:

    • Rated current draw (amps) and rated no-load speed (RPM) indicate the normal condition of the starter motor.
    • Low speed (RPM) and high current draw (amps) indicate too much friction, causing the armature to drag. This can result from one or more of the following conditions:
       - Tight, dirty, or worn bushings or bearings
       - Grounded or shorted armature
       - Grounded field windings
    • Failure to operate (0 RPM), with high current draw (amps), indicates one or more of the following conditions:
       - Shorted field windings
       - Shorted starter terminal
       - Seized bearings
    • Failure to operate (0 RPM), with low or no current draw (amps), indicates one or more of the following conditions:
       - An open field circuit
       - An open in the armature coils
       - Broken brush springs
       - Worn brushes
       - High insulation between the commutator bars or other causes which would prevent contact between brushes and commutator.
    • Low speed (RPM) and low current draw (amps), indicates a high internal resistance caused by one or more of the following conditions:
       - Poor electrical connections
       - Defective electrical leads
    • High, no load speed (RPM) and high current draw (amps) indicates shorted field windings.