We have a 2008 S80 with keyless entry. Today, it decided it wouldn't recognize my keyfob for unlocking, although it was fine with starting the car. I found, in further tests, that I could use the lock/unlock buttons; and then it started recognizing the keyfob for unlocking by pulling the handle on a door and locking by pushing the buttons. So the keyfob probably needs a new battery.

But the puzzling part, and what has me posting here, is that it was locking by itself when the keyfob was 20 feet away, inside the house. I was cleaning the windows (the tree over the driveway drops pitch this time of year), and the car was randomly locking up. I thought maybe I was butt-locking it, so put the keyfob in the back entryway = and the car locked itself again, a couple of times.

I am puzzled.