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Home >> Saturn >> 2009 >> Sky Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 2.4L - Troubleshooting & Diagnosis >> Fuel Injector Circuit Diagnosis >> Circuit/System Testing

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at a fuel injector.
  2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 1 and ground.
    • If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test or replace the fuel injector.
  3. Ignition OFF, connect a J 44603:  Lamp between the control circuit terminal 2 and the ignition circuit terminal 1 of each fuel injector one at a time.
  4. Engine cranking, the test lamp should flash for each injector.
    • If the test lamp is always ON, test the appropriate control circuit for a short to ground. If the circuit tests normal, replace the engine control module (ECM).
    • If the test lamp is always OFF, test the appropriate control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
  5. If all circuits test normal, test or replace the fuel injector. Refer to Fuel Injector Diagnosis (With J39021 or With Tech 2)  or Fuel Injector Diagnosis (with/SA9182E or With/Tech 2)  or Fuel Injector Diagnosis (With CH47976) .
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