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Circuit/System Testing

  1. Ignition ON, engine OFF. Disconnect the generator harness connector.
  2. Measure the voltage of the generator turn on signal circuit terminal 1. Verify the circuit has less than 1 volt.
    • If greater than the specified value, test the generator turn on signal circuit for a short to voltage, or replace the ECM.
  3. Engine running. Measure the voltage of the generator turn on signal circuit terminal 1. Verify the circuit has greater than 3.5 volts.
    • If less than 3.5 volts, test the generator turn on signal circuit for a short to ground, an open or a high resistance, or replace the ECM.
  4. Refer to Charging System Test .
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