On Board Diagnosis Logic

To judge the malfunction, the output from the heated oxygen sensor 1 is monitored to determine whether the rich output is sufficiently high, and lean output is sufficiently low. When both the outputs are shifting to the rich side, the malfunction will be detected.

Fig 1: On Board Diagnosis Logic (1 Of 2)

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

Fig 2: On Board Diagnosis Logic (2 Of 2)

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