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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the generator.
  2. Ignition OFF, test for B+ between the generator sense circuit terminal D and ground.
    • If less than the specified range, test the generator sense circuit for a short to ground, an open/high resistance.
  3. Ignition ON, test for less than 1 volt between the generator turn on signal terminal B and ground.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Engine running, test for greater than 3.5 volts between the generator turn on signal and ground.
    • If less than the specified range, test the signal circuit for a short to ground, an open/high resistance. If the circuit tests normal, replace the ECM.
  5. If the circuit test normal, replace the generator.
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