DTC Detection Logic

The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst (manifold) causes the longer switching time.

MALFUNCTION 1

To judge the malfunctions of heated oxygen sensor 2, ECM monitors whether the voltage is unusually high during various driving conditions such as fuel cut.

Courtesy of NISSAN NORTH AMERICA, INC.

: 1.3 V

MALFUNCTION 2

To judge the malfunctions of heated oxygen sensor 2, ECM monitors whether the minimum voltage of sensor is sufficiently low during various driving conditions such as fuel-cut.

Courtesy of NISSAN NORTH AMERICA, INC.

An excessively high voltage from the sensor is sent to ECM.
The minimum voltage from the sensor is not reached to the specified voltage.

DTC	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
P0138	HO2S2 (B1) (O2 sensor circuit high voltage bank 1 sensor 2)	1	Diagnosis condition	-
			Signal (terminal)	Voltage signal transmitted from heated oxygen sensor 2 to ECM
			Threshold	An excessively high voltage from the sensor is sent to ECM
			Diagnosis delay time	-
		2	Diagnosis condition	-
			Signal (terminal)	Voltage signal transmitted from heated oxygen sensor 2 to ECM
			Threshold	The minimum voltage from the sensor is not reached to the specified voltage
			Diagnosis delay time	-
P0158	HO2S2 (B2) (O2 sensor circuit high voltage bank 2 sensor2)	1	Diagnosis condition	-
			Signal (terminal)	Voltage signal transmitted from heated oxygen sensor 2 to ECM
			Threshold	An excessively high voltage from the sensor is sent to ECM
			Diagnosis delay time	-
		2	Diagnosis condition	-
			Signal (terminal)	Voltage signal transmitted from heated oxygen sensor 2 to ECM
			Threshold	The minimum voltage from the sensor is not reached to the specified voltage
			Diagnosis delay time	-