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Home >> Hyundai >> 2017 >> Sonata Plug-In Hybrid >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (PHEV) (2 Of 3) >> DTC P0401: Exhaust Gas Recirculation Flow Insufficient Detected >> DTC Information >> DTC Detecting Condition

DTC Information: DTC Detecting Condition

Item Detecting Condition Possible Cause
DTC Strategy
  • Signal monitoring
  1. Poor connection or damaged harness
  2. EGR cooler clogging
  3. EGR pipe clogging and leakage
  4. Intake manifold air leak
  5. EGR actuator stuck
Enable Conditions
  • Fuel cut - Off condition
  • Intake air temperature is greater than -6.75 °C (19.85°F)
  • Engine coolant temperature is greater than 55 °C (131°F)
  • Engine speed is between 1088 RPM and 2016 RPM
  • Moving mean value of engine speed gradient is between -192 RPM/s and 192 RPM/s
  • Engine speed gradient is between -416 RPM/s and 416 RPM/s
  • Barometric pressure is greater than 74kPa
  • Battery voltage is between 11V and 16V
  • Measured intake manifold pressure is greater than 10kPa
  • Throttle position is between 0° to 23.8~24.1° (Depends on engine RPM and intake air temperature.)
  • EGR valve position study is completed
  • EGR recirculation flow is higher than 5kg/h
Threshold Value
  • Comparing the reference pressure and a measured pressure is greater than 1.45
  • Intake manifold pressure is less than 41~112kPa (EGR valve close)
Diagnostic Time
  • Fuel cut-off duration 10 sec.
MIL On Condition
  • 2 Drive Cycles