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Home >> Mazda >> 2021 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (3 Of 6) >> DTC P0403-00: EGR Valve Control Circuit Problem >> Notes
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DTC P0403-00: EGR Valve Control Circuit Problem: Notes

DTC P0403:00 DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0403:00 EGR valve control circuit problem
DETECTION CONDITION
  • The PCM monitors the input voltage from the EGR valve. If the voltage remain low or high, the PCM determines that the EGR valve circuit has a malfunction.

    Diagnostic support note

  • This is a continuous monitor (CCM).
  • The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle. (The check engine light may be illuminated depending on the malfunction conditions.)
  • FREEZE FRAME DATA/Snapshot data is available.
  • DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION
  • Inhibits the EGR control.
POSSIBLE CAUSE
  • EGR valve connectors or terminals malfunction
  • Short to ground or open circuit in EGR valve power supply circuit
    • Short to ground in wiring harness between the following terminals:
      • ENGINE1 15 A fuse-EGR valve terminal C
      • ENGINE1 15 A fuse-EGR valve terminal D
    • ENGINE1 15 A fuse malfunction
    • Open circuit in wiring harness between the following terminals:
      • Main relay terminal C-EGR valve terminal C
      • Main relay terminal C-EGR valve terminal D
      • Short to ground in wiring harness between the following terminals:
        • EGR valve terminal A-PCM terminal 1J
        • EGR valve terminal E-PCM terminal 1Y
        • EGR valve terminal B-PCM terminal 1O
        • EGR valve terminal F-PCM terminal 1T
  • PCM connector or terminals malfunction
  • Short to power supply in wiring harness between the following terminals:
    • EGR valve terminal A-PCM terminal 1J
    • EGR valve terminal E-PCM terminal 1Y
    • EGR valve terminal B-PCM terminal 1O
    • EGR valve terminal F-PCM terminal 1T
  • EGR valve circuits are shorted to each other
  • Open circuit in wiring harness between the following terminals:
    • EGR valve terminal A-PCM terminal 1J
    • EGR valve terminal E-PCM terminal 1Y
    • EGR valve terminal B-PCM terminal 1O
    • EGR valve terminal F-PCM terminal 1T
  • EGR valve malfunction
  • PCM malfunction
G13697876Courtesy of MAZDA MOTORS CORP.