It solved my engine light for a day until it came back on and then it was my cat i needed to replace. Mine was the Bank 2 sensor 2 which is the drivers side rear sensor.
there are 4 o2 sensors in total, Bank 1 is passenger side, bank 2 is drivers side, and both sides have a front and rear sensor. So my code was 22, bank 2, sensor 2.
When your under the car you can see both rear sensors, they are only about 2ft apart, im not sure where the o2 sensors are before the CAT.
Heres a link:
http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&item=290127898290
it just has a picture of what you would be looking for under the car.
Hope this helps