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HOMESERVICE MANUALSMAZDA20086 S SPORT, 4D HATCHBACK, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT VARIANT/TRIMSECTION 18 (ON-BOARD DIAGNOSTIC (ENGINE CONTROL SYSTEM L3) (3 OF 5))DTC P0140 [L3]NOTES
2008 Mazda 6 s Sport, 4D Hatchback, Standard

DTC P0140 [L3]: Notes

2008 Mazda 6 s Sport, 4D Hatchback, StandardSECTION Notes
WARNING: This page is about a different variant/trim than selected.
DTC P0140 [L3] DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0140 Rear HO2S circuit no activity detected
DETECTION CONDITION 
  • The PCM monitors the input voltage from the rear HO2S when the following conditions are met. Under the following monitoring conditions, if the input voltage from the rear HO2S does not even exceed 0.55 V though the short term fuel trim is controlled up to 25%  for 9.6 s,  the PCM determines that sensor circuit is not activated.

    MONITORING CONDITIONS 

    • HO2S, HO2S heater and TWC repair verification drive mode
    • Following conditions are met for above 20.8 s 
      • Engine speed is above 1, 500 RPM. 
      • Engine coolant temperature is above 70 °C {158 °F}. 
    • Rear HO2S voltage is above 0.1 V 

Diagnostic support note 
  • This is an intermittent monitor (HO2S).
  • 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.
  • DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Rear HO2S deterioration
  • Rear HO2S heater malfunction
  • Exhaust system leakage
  • Open or short to ground circuit between rear HO2S terminal A and PCM terminal 2Q
  • Insufficient compression
  • Engine malfunction
G04324024Courtesy of MAZDA MOTORS CORP.
RENDER: 1.0x

NO RELATED

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