Starter Motor Ground Circuit Check
WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
For information on Ford Color Coded Illustrations refer to OEM COLOR CODING INFORMATION
NOTE:
Always make the multi meter connection at the component terminal rather than at the wiring end of the connector. Making a connection at the wiring end of the connector could result in false readings because the meter will not pick up a high resistance between the wiring connector and component.
- Make sure the battery is fully charged. For additional information, refer to: Battery .
- Perform a battery drain test. For additional information, refer to: Battery Drain Check .
- Connect a remote starter switch between starter solenoid "S" terminal and the battery positive terminal.
- Connect the multimeter positive lead to the starter motor housing (the connection must be clean and free of rust or grease). Connect the negative lead to the negative battery terminal.
- Place gear selector lever in Park or Neutral.
- Engage the remote starter switch and crank the engine. Read and record the voltage reading. The reading should be 0.5 volt or less.
- If the voltage reading is greater than 0.5 volt, clean the negative cable connections at the battery, the body ground connections and the starter ground connection. Retest.
- If the voltage reading is greater than 0.5 volt, install a new negative battery cable. For additional information, refer to: Battery Cables - 2.7L EcoBoost (238kW/324PS) .
- If the voltage reading is less than 0.5 volt and the engine still cranks slowly, install a new starter motor. For additional information, refer to: Starter Motor .