P0136 error code
 

I had my 2004 Camry XLE checked for a check engine light. It came up P0136 code for O2 Sensor Circut Bank 1 Sensor 2. From my own research I am assuming the sensor is on the exhaust pipe, before the Cat. My question is, on partsgeek.com, it shows a few different sensors for the 2.4 4cyl, but I dont know which one it is. Can anyone steer me in the right direction so I buy the right one? Thanks in advance for any help.

Steve

Sensor 1 is first sensor on exhaust before the first CAT. Sensor 2 is after this CAT. Also called downstream sensor.