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HOMESERVICE MANUALSMAZDA20105 SPORT, 2.3 L, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 550 (ON-BOARD DIAGNOSTIC [ENGINE CONTROL SYSTEM L3))DTC P0031 [L3]NOTES
2010 Mazda 5 Sport, 2.3 L, Standard

DTC P0031 [L3]: Notes

2010 Mazda 5 Sport, 2.3 L, StandardSECTION Notes
WARNING: This page is about a different car, the 2008 Mazda 5. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0031 [L3] DETECTION CONDITIONS AND POSSIBLE CAUSES

DTC P0031 Front HO2S heater circuit low input
DETECTION CONDITION 
  • The PCM monitors the front HO2S heater output voltage at PCM terminal 2A. If the PCM turns the front HO2S heater to OFF but the front HO2S heater circuit voltage is below 5 V  for 2 s  , the PCM determines that the front HO2S heater circuit has malfunction.
    NOTE:
    • The front HO2S heater is controlled by duty signal.

Diagnostic support note 
  • This is a continuous monitor (HO2S heater).
  • 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 
  • Front HO2S malfunction
  • Open circuit in wiring harness between main relay and front HO2S terminal A
  • Open circuit in wiring harness between front HO2S terminal E and PCM terminal 2A
  • Short to ground in wiring harness between front HO2S terminal E and PCM terminal 2A
  • Poor connection at front HO2S or the PCM connector
  • PCM malfunction
G05542941
RENDER: 1.0x

NO RELATED

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