We are into one of those areas where the PC/ED is a little hazy..... The list of possible causes is a little sparse and fails to include some conditions that could set the code.
In the grand scheme of things, one could inspect the sensor and wiring for anything obvious and then, if everything looks Kosher, replace the downstream sensor as part of the diagnostic process.... One has to assign a dollar value to their DIY diagnostic time to justify this.
In essence, this code indicates low output voltage from HO2-2.. the downstream sensor on the passengers side. What we see is that there is a lot of O2 in what's coming out of the cat.... this could mean that the Cat is bad, it could mean that there is an exhaust leak.... it could mean a lot of things. I have been the victim of customers saying "I didn't think that mattered" too many times.... Without knowing anything else abot the car, it's tough to form a reasonable reply.
Sidebar.... I chased one customer away several years ago.... His pick up had developed one nasty habit or another (can't remember quite what it was) and he refused to pay me to scan codes and data stream. His check engine light had come on about a year earlier and still ran "pretty good". That, to him, meant that this new problem had nothing to do with the check engine light.... and these people are allowed to vote.....
At any rate.... if the original poster is bent on changing this sensor.. the best tool I have so far found in a 7/8ths inch line wrench (providing you can get it in to where you need.... ). The sensor is on the drivers side after the cat.... they come out easier when things are hot....
If it was as simple as it looks, I'd be collecting welfare....