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HOMESERVICE MANUALSCHEVROLET2003TRAILBLAZER 4.2 S, 4WDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 109 (ENGINE CONTROL SYSTEM SELF-DIAGNOSTICS - 3.4L)DIAGNOSTIC TESTSDTC P0401: EGR SYSTEMCONDITIONS FOR RUNNING DTC
2003 Chevrolet TrailBlazer 4.2 S, 4WD

Conditions For Running DTC

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Conditions For Running DTC
WARNING: This page is about a different car, the 2002 Pontiac Grand Am, 2002 Oldsmobile Alero, 2002 Chevrolet Monte Carlo, and 2002 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
  • DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0121, P0122, P0123, P0201-P0206, P0300, P0336, P0403, P0404, P0405, P0502, P0503, P0506, P0507, P1106, P1107, P1111, P1112, P1114, P1115, P1121, P1122, P1374, or P1404 are not set.
  • The system voltage is 10-18 volts.
  • The AC status does not change.
  • The transaxle range does not change.
  • The TP angle is less than 1 percent, deceleration.
  • The IAT is more than 176°F (80°C).
  • The ECT is more than 167°F (75°C).
  • The engine speed is 1050-1300 RPM.
  • The IAC position is steady.
  • The MAP is steady between 15-70 kPa.
  • The vehicle speed is more than 35 MPH during deceleration.
  • The BARO sensor less than 70 kPa.
  • The vehicle will need to be driven at greater than 50 MPH, and then allowed to decelerate. When the vehicle is decelerating while meeting all of the criteria listed above, the PCM will enable the test to run. When the test is running, you will see the desired EGR parameter and the EGR position sensor on the scan tool change from 0 to a calibrated value greater than 0.
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