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Home >> Saturn >> 2010 >> Sky Red Line, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 2.0L - DTC P0243 To DTC P0690 >> DTC P0627-P0629 >> Circuit/System Testing
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Circuit/System Testing

  1. Ignition OFF, disconnect the fuel pump relay using the J 43244:  Pliers.
  2. Connect a test lamp between the control circuit terminal 86 of the fuel pump relay and ground.
  3. Ignition ON, command the fuel pump relay ON and OFF with a scan tool. The test lamp should turn ON and OFF as commanded.
    • If the test lamp remains OFF all the time, test for a short to ground or an open/high resistance on the control circuit. If the circuit/connections test normal, replace the ECM.
    • If the test lamp remains ON all the time, test for a short to voltage on the control circuit. If the circuit/connections test normal, replace the ECM.
  4. Ignition OFF, connect a test lamp between the fuel pump relay control circuit terminal 86 and the ground circuit terminal 85 of the fuel pump relay.
  5. Ignition ON, command the fuel pump relay ON and OFF with a scan tool. The test lamp should turn ON and OFF as commanded.
    • If the test lamp does not turn ON when commanded, repair the open/high resistance in the ground circuit of the fuel pump relay.
  6. Ignition ON, test for 2-3 V on the control circuit terminal 86 of the fuel pump relay.
    • If not within the specified range, replace the ECM.
  7. If all circuits/connections test normal, test or replace the fuel pump relay.
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