LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Pontiac >> 2002 >> Aztek AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics >> Diagnostic Tests >> DTC P0412: Secondary Air Injection Relay Control Circuit >> Diagnostic Procedures
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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. Turn ON the ignition. Use a scan tool in order to command the AIR solenoid ON and OFF. Does the solenoid turn ON and OFF with each command? If yes, see DIAGNOSTIC AIDS . If no, go to next step.
  3. Turn OFF the ignition. Disconnect the solenoid. Turn ON the ignition. Probe the feed circuit with a test lamp that is connected to a good ground. Does the test lamp illuminate? If yes, go to next step. If no, go to step  10.
  4. Connect a test lamp between the control circuit and the feed circuit. Use a scan tool in order to command the AIR solenoid ON and OFF. Does the test lamp turn ON and OFF with each command? If yes, go to step  8. If no, go to next step.
  5. Does the test lamp remain illuminated with each command? If yes, go to step  7. If no, go to next step.
  6. Test the control circuit for a short to voltage or an open. Did you find and correct the condition? If yes, go to step  13. If no, go to step  9.
  7. Test the control circuit for a short to ground. Did you find and correct the condition? If yes, go to step  13. If no, go to step  9.
  8. Test for poor connections at the solenoid. Did you find and correct the condition? If yes, go to step  13. If no, go to step  11.
  9. Test for poor connections at the control module. Did you find and correct the condition? If yes, go to step  13. If no, go to step  12.
  10. Repair the open or short to ground in the feed circuit. After repairs, go to step  13.
  11. Replace the solenoid. After repairs, go to step  13.
  12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After repairs, go to next step.
  13. 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 as specified in the supporting text. Does the DTC run and pass? If yes, go to next step. If no, go to step  2.
  14. 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.
scientia non olet · About LEMON Manuals