2006 Mazda 6 MazdaspeedFACTORY OEM SERVICE PROCEDURE

DTC P0203: Notes

DTC P0203 DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0203 Injector circuit/open cylinder No.
DETECTION CONDITION 
  • If the fuel injection verification signal is not input at 255 times  continuously even though the PCM drives fuel injector No., he PCM determines that there is an open circuit in the fuel injector No. control circuit.

    MONITORING CONDITION 

    • The following conditions are met:
      • Engine speed: 4, 00 RPM or less 
      • Battery voltage: 10.03 V or more 
      • Fuel injection control: except during fuel cut

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition during first drive cycle.
  • FREEZE FRAME DATA is available.
  • DTCs are stored in the PCM memory.
POSSIBLE CAUSE 
  • Fuel injector No. malfunction
  • Injector driver module malfunction
  • Connector or terminal malfunction
  • Open circuit between fuel injector No. terminal B and injector driver module terminal 1A
  • Open circuit between fuel injector No. terminal A and injector driver module terminal 1C
  • Short to power supply between fuel injector No. terminal A and injector driver module terminal 1C
  • Short to ground between fuel injector No. terminal B and injector driver module terminal 1A
  • Short to ground between fuel injector No. terminal A and injector driver module terminal 1C
  • PCM malfunction
G04324113Courtesy of MAZDA MOTORS CORP.
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