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HOMESERVICE MANUALSMAZDA20086 S SPORT, 4D HATCHBACK, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 589 (ON-BOARD DIAGNOSTIC [ENGINE CONTROL SYSTEM L3 WITH TC])DTC P0030NOTES
2008 Mazda 6 s Sport, 4D Hatchback, Standard

DTC P0030: 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 P0030 DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0030 Front HO2S heater control circuit problem
DETECTION CONDITION 
  • OBD system monitors the output signal voltage from oxygen sensor which is in proportion to the element impedance of oxygen sensor. If the output signal voltage is not between 0.75 V  and 1.5 V  after specified time from engine start, heater performance is considered failed.

Monitoring condition 
  • 74 s  elapsed from engine start
  • Battery voltage: 10-18 V 

Diagnostic support note 
  • This is an intermittent monitor (HO2S heater).
  • The 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.
  • DTCs are stored in the PCM memory.
POSSIBLE CAUSE 
  • Front HO2S heater malfunction
  • Connector or terminal malfunction
  • Open circuit in wiring harness between front HO2S heater terminal 2D and PCM terminal 4AD
  • Short to ground in the wiring harness between front HO2S heater terminal 2D and PCM terminal 4AD
  • Short to power supply in the wiring harness between front HO2S heater terminal 2D and PCM terminal 4AD
  • Open circuit in the wiring harness between front HO2S heater terminal 1B and PCM terminal 2G
  • PCM malfunction
RENDER: 1.0x

NO RELATED

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