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Home >> Pontiac >> 2002 >> Aztek AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics >> Diagnostic Tests >> DTC P0030: Ho2S Heater Control Circuit Sensor 1 >> Diagnostic Procedures
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Diagnostic Procedures

  1. Did you perform the Diagnostic System Check-Engine Controls? If yes, go to next step. If no, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
  2. Allow the engine to idle at operating temperature. Monitor the HO2S 1 Heater Current parameter on a scan tool. Allow the current to stabilize. Is the HO2S 1 Heater Current 0.25-0.85 amp.? If yes, go to next step. If no, go to step  4.
  3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see INTERMITTENT CONDITIONS  under SELF-DIAGNOSTIC SYSTEM.
  4. Turn OFF the ignition. Disconnect the HO2S 1. Start the engine. Allow the engine to idle at operating temperature. Monitor the scan tool for at least 30 seconds. Does the DTC fail this ignition cycle? If yes, go to next step. If no, go to step  6.
  5. Test the HO2S 1 heater low control circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  10. If no, go to step  7.
  6. Check for poor connections at the harness connector of the HO2S 1. Did you find and correct the condition? If yes, go to step  10. If no, go to step  8.
  7. Check for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step  10. If no, go to step  9.
  8. Replace the HO2S 1. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step  10.
  9. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After repairs, go to next step.
  10. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step  2.
  11. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
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