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DTC P0403: Notes

DTC P0403 DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0403 EGR valve (stepper motor) circuit problem
DETECTION CONDITION 
  • The PCM monitors the input voltage from EGR valve. If voltage at PCM terminals 2AU, 2AR, 2AY and/or 2AV remain low or high, the PCM determines that the EGR valve circuit has malfunction.

    • Diagnostic support note 

  • This is a continuous monitor (CCM).
  • MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
  • PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • EGR valve malfunction
  • Connector or terminal malfunction
  • Short to power supply in wiring harness between EGR valve terminal E and PCM terminal 2AU
  • Short to power supply in wiring harness between EGR valve terminal A and PCM terminal 2AR
  • Short to power supply in wiring harness between EGR valve terminal B and PCM terminal 2AY
  • Short to power supply in wiring harness between EGR valve terminal F and PCM terminal 2AV
  • Short to ground circuit in wiring harness between EGR valve terminal E and PCM terminal 2AU
  • Short to ground circuit in wiring harness between EGR valve terminal A and PCM terminal 2AR
  • Short to ground circuit in wiring harness between EGR valve terminal B and PCM terminal 2AY
  • Short to ground circuit in wiring harness between EGR valve terminal F and PCM terminal 2AV
  • Open circuit in wiring harness between EGR valve terminal E and PCM terminal 2AU
  • Open circuit in wiring harness between EGR valve terminal A and PCM terminal 2AR
  • Open circuit in wiring harness between EGR valve terminal B and PCM terminal 2AY
  • Open circuit in wiring harness between EGR valve terminal F and PCM terminal 2AV
  • Open circuit in wiring harness between main relay terminal D and EGR valve terminal C
  • Open circuit in wiring harness between main relay terminal D and EGR valve terminal D
  • PCM malfunction
G04315721
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