the PO139 code says that bank 1 sensor 2 needs replacing. Where is it located ?

Question

The OBD reader code PO139 says bank 1 sensor 2 needs replacing. Where is it located?

Answer 1

P0139 - Oxygen sensor Bank 1 sensor 2 slow response

Bank 1 is where cylinder 1 is located, when you have sensor 2 this is considered downstream , or a catalytic monitor sensor,The catalytic monitor 02 sensor, is threaded into the catalytic convertor