Catalyst Location

WARNING: This page is about a different car, the 2012 Lexus IS 350. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Catalyst System Efficiency Below Threshold Location

NOTE:

When outputting DTC P0420 replace the exhaust manifold sub-assembly RH and the front exhaust pipe assembly together when catalyst replacement is necessary (Excluding air fuel ratio sensor and heated oxygen sensor).
When outputting DTC P0430 replace the exhaust manifold sub-assembly LH and the front exhaust pipe assembly together when catalyst replacement is necessary (Excluding air fuel ratio sensor and heated oxygen sensor).