An signal, in the form of an exclamation mark, is appearing on my dashboard. What does that mean?

You need to add air into your tires. put 36psi on all 4 tires and drive vehicle for about 2 miles or less at at least35mph and if all sensors and systems are ok, light will go out. if only 1 tire os low and other 3 are not, than you may have a nail in the tire causing a leak, which causes low pressure, which causes the light to come on. start with adding air to 36 pounds to aall 4 tires.