Dreading taking the Alltrack back to the dealer 3 months after buying it new, I lived with this message and low tire pressure idiot light for a week. Naturally I checked the pressure with a gauge when it was triggered, and finding it to be within spec, I decided the car’s right rear tire pressure sensor was bad.
Then yesterday I remembered something in the menus: tire pressure calibration. I did it, and the message is of course gone. Whew.