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Home >> Pontiac >> 2001 >> Aztek Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics >> Diagnostic Tests >> DTC P0412: Secondary Air Injection Pump Relay Control Circuit >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform powertrain diagnostic system check. See POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
  2. Turn ignition on. Using scan tool, command AIR relay on and off. If relay turns on and off with each command, see DIAGNOSTIC AIDS . If relay does not turn on and off with each command, go to next step.
  3. Turn ignition off. Remove AIR pump relay (located on right front of engine compartment, behind horn). Turn ignition on. Using a test light connected to ground, probe AIR pump relay harness connector terminal No. 85 (Pink wire). See WIRING DIAGRAMS article. If test light illuminates, go to next step. If test light does not illuminate, go to step  10.
  4. Connect test light between AIR pump relay harness connector terminals No. 85 (Pink wire) and No. 86 (Brown wire). Using scan tool, command AIR solenoid on and off . If test light turns on and off with each command, go to step  8. If test light does not turn on and off with each command, go to next step.
  5. If test light remains on with each command, go to step  7. If test light does not remain on with each command, go to next step.
  6. Turn ignition off. Check for short to voltage or open circuit in Brown wire between relay harness connector terminal No. 86 and PCM harness connector C2 terminal No. 75. Repair as necessary. After repairs, go to step  13. If circuit is okay, go to step  9.
  7. Turn ignition off. Check for short to ground in Brown wire between relay harness connector terminal No. 86 and PCM harness connector C2 terminal No. 75. Repair as necessary. After repairs, go to step  13. If circuit is okay, go to step  9.
  8. Turn ignition off. Check for poor connections at AIR pump relay harness connector. Repair as necessary. After repairs, go to step  13. If connections are okay, go to step  11.
  9. Check for poor connections at PCM harness connector. Repair as necessary. After repairs, go to step  13. If connections are okay, go to step  11.
  10. Turn ignition off. Repair for open or short to ground in AIR solenoid feed circuit. After repairs, go to step  13.
  11. Replace AIR solenoid. After replacing solenoid, go to step  13.
  12. Replace PCM. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  13. Turn ignition on, with engine off. Using scan tool, clear DTCs. Turn ignition off for 30 seconds. Operate vehicle within the conditions for running this DTC. See CODE ENABLE CRITERIA . If DTC runs and passes, go to next step. If DTC resets, go to step  2.
  14. Using scan tool, observe the stored information and CAPTURE INFO. If scan tool displays any undiagnosed DTCs, diagnose affected DTCs. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are displayed, system is okay.
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