Details On DTCs

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DTC P0138:00 (PCM, SKYACTIV-G, US) DETECTION CONDITION AND POSSIBLE CAUSE

Description	HO2S circuit high input
Detection condition	Determination conditions	A condition in which the HO2S input voltage exceeds the specified value continues for the specified period.
	Preconditions	Not applicable
	Malfunction determination period	5 s period
	Drive cycle	2
	Self test type	CM DTC self test, KOEO self test, KOER self test
	Sensor used	HO2S
Fail-safe function	Not applicable
Vehicle status when DTCs are output	Not applicable
Possible cause	HO2S connector or terminals malfunction PCM connector or terminals malfunction Short to power supply in HO2S signal circuit HO2S malfunction PCM malfunction
Courtesy of MAZDA MOTORS CORP.