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HOMESERVICE MANUALSMAZDA20086 S SPORT, 4D HATCHBACK, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 687 (ON-BOARD DIAGNOSTIC (ENGINE CONTROL SYSTEM L3) (2 OF 5))DTC P0043NOTES
2008 Mazda 6 s Sport, 4D Hatchback, Standard

DTC P0043: 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 P0043 DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0043 Rear HO2S heater circuit low input
DETECTION CONDITION 
  • The PCM monitors the rear HO2S heater control voltage when the PCM turns the rear HO2S heater off. If the control voltage exceeds 25%  of the battery voltage, the PCM determines that the rear HO2S heater control circuit voltage is low.

Diagnostic support note 
  • This is a continuous monitor (HO2S heater).
  • MIL illuminates if PCM detects above malfunction condition in two consecutive drive cycles or in one drive cycle while DTC for the same malfunction has been stored in PCM.
  • PENDING CODE is available if PCM detects the above malfunction condition during first drive cycle.
  • FREEZE FRAME DATA is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Rear HO2S heater malfunction
  • Connector or terminal malfunction
  • Short to power supply in wiring harness between rear HO2S terminal D and PCM terminal 2BE
  • PCM malfunction
G04324004Courtesy of MAZDA MOTORS CORP.
RENDER: 1.0x

NO RELATED

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