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Starter Motor Troubleshooting


09 Sep 2019

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If a new starter motor has been installed and the starting problem still persists, it is imperative to swiftly check the vehicle voltage. To do this safely and accurately, technicians are advised to follow the steps below:

  1. Install the starter motor and ensure that all electrical connections are securely fastened.
  2. Connect the voltmeter to the starter motor. Black lead should be attached to the starter frame/case, while the red lead should lead to the “S” terminal.
  3. If the voltage reading is less than 12 volts and the engine does not crank, check for a weak battery, poor ground connection, bad ignition switch or defective neutral safety switch.
  4. If the engine does not crank, but the voltage reading is more than 12V, the technician should consider moving the red wire of the voltmeter to the starter B+ terminal and observe the voltmeter reading when attempting to crank the engine again – no crank and a voltage reading lower than 12V can mean that there is a weakened battery, or loose/corroded cable.
  5. If the engine does not crank and the voltmeter reads over 9 volts, this could indicate a faulty new starter.

WARNING: Always practice extreme caution when working with an operating engine.

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