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Circuit/System Testing

LSA or LF1 Engine

  1. Verify that a test lamp illuminates between the generator B+ and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  2. Ignition OFF, disconnect the X1 harness connector at the generator.
  3. Ignition ON, test for 4.5-5.5 V between the control circuit terminal 1 and ground.
    • If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
    • If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal replace the ECM.
  4. If the circuits test normal, replace the generator.

LLT Engine

  1. Verify that a test lamp illuminates between the generator B+ X2 and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  2. Ignition OFF, disconnect the X1 harness connector at the generator.
  3. Ignition ON, test for less than 1 V between the control circuit terminal 1 and ground.
    • If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Engine running, test for greater than 3.5 V between the control circuit terminal 1 and ground.
    • If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal replace the ECM.
  5. If the circuits test normal, replace the generator.
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