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Home >> Saturn >> 2008 >> Astra XR, 2D Hatchback, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - DTC P000A To DTC P0365 >> DTC P0030-P0032, or P0135 >> Circuit/System Testing

Circuit/System Testing

You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Ignition OFF, disconnect the harness connector at the HO2S 1.
  2. Ignition ON, verify that a test lamp illuminates between the HO2S 1 heater voltage supply circuit terminal 3 and ground.
    • If the test lamp does not illuminate, test the HO2S 1 heater voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and its fuse is open, test all components connected to the fuse and replace as necessary.
  3. Ignition ON, verify that a test lamp does not illuminate between the HO2S 1 heater low control circuit terminal 1 and the HO2S 1 heater voltage supply circuit terminal 3.
    • If the test lamp illuminates, test the HO2S 1 heater low control circuit for a short to ground. If the circuit tests normal, replace the ECM.
  4. Engine running, leave the test lamp connected from the previous step. The lamp should flash or be ON steady.
    • If the test lamp is not ON steady or flashing, test the HO2S 1 heater low control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
  5. If the ECM and all circuits test normal, replace the HO2S 1.
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