First scroll through the right button on the information pad left of the steering wheel on the dash until you get to tire pressure (front then back). Check and see which sensor is not reading or tire is low. Make note of that. If it is a low pressure problem just fill the tire up with air and the light will extinguish. If that doesn't do it, then you have to take the car to a mechanic with a registration tool, and the car will be put into learn mode and the sensors reset with the tool. Dealer is probably the best place to get this done. That doesn't mean you are done. Most likely at least one of your sensors is bad in the wheel. That will have to be replaced, which is why you need to know which one is acting up.