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Home >> Mazda >> 2017 >> CX-9 Signature >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (2 Of 5) >> DTC P0401-00; EGR Flow Insufficient Detected >> Notes
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DTC P0401-00; EGR Flow Insufficient Detected: Notes

NOTE:
  • To determine the malfunctioning part, proceed with the diagnostics from "Function Inspection Using M-MDS".

Details On DTCs

DETECTION CONDITION AND POSSIBLE CAUSE

DESCRIPTION EGR flow insufficient detected
DETECTION CONDITION Determination conditions
  • When the following condition is met, the EGR volume is lower than the specification for the target value for a continuous specified time.
Preconditions
  • During EGR control
  • Engine speed: 1, 200-2, 500 rpm
  • Fuel injection amount: 4-50 mm3 /stoke
  • Engine torque: 20-240 N.m {2.1-24 kgf.m, 15-177 ft.lbf}
  • The following DTCs are not detected:
    • MAP sensor: P0107:00, P0108:00
    • MAF sensor: P0102:00, P0103:00
    • Exhaust gas pressure sensor: P0472:00, P0473:00
    • EGR valve control system: P0403:00
      • Fuel injector: P0201:00, P0202:00, P0203:00, P0204:00
Drive cycle
  • 2
Self test type
  • CMDTC self test
Sensor used
  • EGR valve
  • MAF sensor
  • MAP sensor
  • Exhaust gas pressure sensor
FAIL-SAFE FUNCTION
  • Not applicable
VEHICLE STATUS WHEN DTCs ARE OUTPUT
  • The following vehicle conditions differ depending on the type of malfunction
    • Illuminates the check engine light
POSSIBLE CAUSE
  • Erratic signal to PCM
    • MAF sensor signal malfunction
    • MAP sensor signal malfunction
    • Input signal part connector or terminals malfunction
      • Input signal part related circuit malfunction
  • EGR valve malfunction (stuck close)
  • Air suction in intake air system between dynamic pressure turbo (DPT) and intake manifold
  • EGR system passage malfunction (restriction)
  • Exhaust gas pressure sensor malfunction
  • PCM malfunction