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Home >> Pontiac >> 2009 >> G8 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System & Fuel System - 3.6L - DTC P0008 To DTC P0277 >> DTC P0053 or P0059 >> Circuit/System Testing
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Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
  1. Ignition OFF, disconnect the harness connector at the appropriate HO2S.
  2. Ignition ON, verify that a test lamp illuminates between the appropriate HO2S heater voltage supply circuit harness connector terminal 1 and ground.
    • If the test lamp does not illuminate, test the HO2S heater voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the HO2S heater voltage supply circuit 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 appropriate HO2S heater voltage supply circuit harness connector terminal 1 and the appropriate HO2S heater low control circuit harness connector terminal 2.
    • If the lamp illuminates, test the HO2S heater low control circuit for a short to ground. If the circuit tests normal, replace the ECM.
  4. Ignition ON, 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 heater low control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
  5. NOTE:
    • The output driver should detect a short to voltage and turn OFF. If a resistance fault is present the driver will remain ON and the scan tool will display more than 0.0 amp. Less than 10 ohms may set a DTC.
    • Performing this test may set additional DTCs.
  6. Ignition OFF, install a 30A fused jumper wire between the appropriate HO2S heater voltage supply circuit harness connector terminal 1 and the appropriate HO2S heater low control circuit harness connector terminal 2.
  7. Engine running, verify the appropriate scan tool HO2S Heater parameter is less than 0.1 amp.
  8. If more than the specified range, test the HO2S heater voltage supply and HO2S heater low control circuits for more than 1 ohm.
    • ECM harness connector X1 terminal 96 and the HO2S B1S1 low reference harness connector terminal 2
    • ECM harness connector X1 terminal 72 and the HO2S B1S1 low reference harness connector terminal 2
    • HO2S heater supply voltage circuit harness connector terminal 1 and the under bonnet electrical centre (UBEC) fuse 33.
  9. If the ECM and all circuits test normal, replace the appropriate HO2S.