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HOMESERVICE MANUALSMAZDA20066 I, 4D SEDAN, AUTOMATICREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCESYSTEMON-BOARD DIAGNOSTIC [ENGINE CONTROL SYSTEM L3)DTC P0138NOTES
2006 Mazda 6 i, 4D Sedan, Automatic

DTC P0138: Notes

2006 Mazda 6 i, 4D Sedan, AutomaticSECTION Notes
DTC P0138 DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0138 Middle(1)/Rear(2) HO2S circuit high input
DETECTION CONDITION 
  • The PCM monitors input voltage from middle(1)/rear(2) HO2S. If the input voltage from the middle(1)\rear(2) HO2S sensor is above 1.2 V for 0.5 s (1) /0.8 s (2)  , the PCM determines that circuit input is high.

Diagnostic support note 
  • This is a continues 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 
  • Middle(1)/Rear(2) HO2S malfunction
  • Short to power supply in wiring harness between middle(1)/rear(2) HO2S terminal A and PCM terminal 2R(1), 2Q(2)
  • Middle(1)/Rear(2) HO2S or PCM terminal shorted
  • PCM malfunction
G04324023Courtesy of MAZDA MOTORS CORP.
(1) California emission regulation applicable ATX model
(2) Except for California emission regulation applicable ATX model
RENDER: 1.0x

NO RELATED

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