On Board Diagnosis Logic

Under the condition in which the heated oxygen sensor 1 signal is not input, the ECM circuits will read a continuous approximately 0.3V. Therefore, for this diagnosis, the time that output voltage is within 200 to 400 mV range is monitored, and the diagnosis checks that this time is not inordinately long.

Fig 1: Graphing Heated Oxygen Sensor 1 Signal For DTC P0134 & P0154 (Correct & Incorrect Example)

Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 2: Identifying DTC P0134 & P0154 Conditions & Possible Causes

Courtesy of NISSAN MOTOR CO., U.S.A.