On Board Diagnosis Logic

WARNING: This page is about a different car, the 2003 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.

For on board diagnosis logic, see Fig 1.

Fig 1: Identifying On Board Diagnosis Logic For DTC P0420 Or DTC P0430: 3-Way Catalyst Function

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