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Home >> Pontiac >> 2001 >> Aztek Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics >> Diagnostic Tests >> DTC P0403: EGR Solenoid 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, with engine off. Using scan tool, command EGR from zero percent to 100 percent. If EGR position sensor remains close to the desired EGR position at all commanded positions, go to next step. If EGR position sensor does not remain close to the desired EGR position at all commanded positions, go to step  4.
  3. Observe the FREEZE FRAME/FAILURE RECORDS data for this DTC. Turn ignition off for 30 seconds. Operate vehicle within the conditions for running this DTC or as close to FREEZE FRAME/FAILURE RECORDS data observed. See CODE ENABLE CRITERIA . If DTC fails this ignition, go to next step. If DTC does not fail this ignition, problem is intermittent.
  4. Turn ignition off. Disconnect EGR solenoid harness connector. Turn ignition on, with engine off. Using a test light connected to ground, probe EGR solenoid harness connector terminal "E" (Red wire). See Figure. Using scan tool, command EGR between 0-10 percent. If test light turns on and off with each command, go to next step. If test light does not turn on and off with each command, go to step  6.
  5. Connect test light between EGR solenoid harness connector terminals "B" (Black wire) and "E" (Red wire). Using scan tool, command EGR between 0-10 percent. If test light turns on and off with each command, go to step  10. If test light does not turn on and off with each command, go to step  9.
  6. If test light remains illuminated with each command, go to step  8. If test light does not remain illuminated with each command, go to next step.
  7. Turn ignition off. Check for short to ground or open in Red wire between EGR solenoid harness connector terminal "E" and PCM harness connector C2 terminal No. 4. Repair as necessary. After repairs, go to step  14. If circuit is okay, go to step  11.
  8. Turn ignition off. Check for short to voltage in Black wire between EGR solenoid harness connector terminal "B" and PCM harness connector C1 terminal No. 31. Repair as necessary. After repairs, go to step  14. If circuit is okay, go to step  11.
  9. Turn ignition off. Check for open or high resistance in Black wire between EGR solenoid harness connector terminal "B" and PCM harness connector C1 terminal No. 31. Repair as necessary. After repairs, go to step  14. If circuit is okay, go to step  11.
  10. Turn ignition off. Check for poor connections at EGR harness connector. Repair as necessary. After repairs, go to step  14. If connections are okay, go to step  12.
  11. Check for poor connections at PCM harness connector. Repair as necessary. After repairs, go to step  14. If connections are okay, go to step  13.
  12. Replace EGR valve. After replacing EGR valve, go to step  14.
  13. Replace PCM. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  14. Turn ignition on, with engine off. Using scan tool, clear DTCs. Turn ignition off for 30 seconds. Operate vehicle within 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.
  15. 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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