D's got about ~82k miles on it now, and the check engine light sprang to life a couple of days ago while on the highway. Got to a rest area and saw that the code was P0551. Of course, the first thing I did was check on the forums here to find out what I've gotten myself into. Most said it's probably a faulty connection on the power steering pressure switch. Also that it's best to replace it before it causes other issues like leaking onto the o2 sensor, etc.
The power steering fluid level was fine and no visible leaks anywhere. So I'm going to follow the wisdom of DOC -- never steered me wrong before. I read it was the easiest fix ever. Rockauto has the part (PSS13) for about $24 shipped. Just wanted to know -- where's the switch located? No one seemed to mention that.