Check engine light diagnosed as replace cat converter bank 2.
Catalytic converter replacement. What side and what part? on 2005 Toyota 4Runner
Bank 2 is where cylinder #2 is located, on your 4Runner that should be on the drivers side. If you look closely at the engine you will find one bank offset slightly in front of the other. The bank offset forward is #1, the rearward bank is #2. This rule works on all v-style engines.