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Circuit/System Testing

WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
  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:  Injector Test 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 (w/CH47976)  or Fuel Injector Diagnosis (w/SA9182E or w/Tech 2) .
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