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HOMESERVICE MANUALSMAZDA20086 S SPORT, 4D HATCHBACK, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 590 (ON-BOARD DIAGNOSTIC [ENGINE CONTROL SYSTEM (AJ])DTC P0403NOTES
2008 Mazda 6 s Sport, 4D Hatchback, Standard

DTC P0403: Notes

2008 Mazda 6 s Sport, 4D Hatchback, StandardSECTION Notes
WARNING: This page is about a different car, the 2007 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0403 [AJ] DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0403 EGR valve (stepper motor) circuit malfunction
DETECTION CONDITION 
  • The PCM monitors the EGR valve control signal voltage and current. If the following conditions are met, the PCM determines that there is the EGR control circuit problem.
    • The PCM turns the EGR valve off, but the voltage of the EGR valve control signal remains low.
    • The PCM turns the EGR valve on, but the current of the EGR valve control signal remains high.

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.
  • DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • EGR valve malfunction
  • Connector or terminal malfunction
  • Open circuit between main relay terminal C and EGR valve terminal C
  • Open circuit between main relay terminal C and EGR valve terminal D
  • Short to ground circuit between EGR valve terminal A and PCM terminal 2R
  • Short to ground circuit between EGR valve terminal B and PCM terminal 2S
  • Short to ground circuit between EGR valve terminal E and PCM terminal 2Q
  • Short to ground circuit between EGR valve terminal F and PCM terminal 2O
  • Short to power circuit between EGR valve terminal A and PCM terminal 2R
  • Short to power circuit between EGR valve terminal B and PCM terminal 2S
  • Short to power circuit between EGR valve terminal E and PCM terminal 2Q
  • Short to power circuit between EGR valve terminal F and PCM terminal 2O
  • Open circuit between EGR valve terminal A and PCM terminal 2R
  • Open circuit between EGR valve terminal B and PCM terminal 2S
  • Open circuit between EGR valve terminal E and PCM terminal 2Q
  • Open circuit between EGR valve terminal F and PCM terminal 2O
  • PCM malfunction
G04324196
RENDER: 1.0x

NO RELATED

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