The message came up that the air pressure in front driver's side was 29 psi, add air. I went to service station and tried to add air. Gauge was stating 35 psi. The next morning it was showing the back driver's side was at 28 psi, same routine at service station. This time I checked all of the tires, none needed air. Since this time, it shows that bothe front and driver's side back need air. I keep trying to reset the computer, but it doesn't happen. Have not taken to dealer yet, but will soon, as there is another problem also.