The sensors for the tire pressure are out of calibration. If you go by the sensor on the car you end up with about 26 psi on your tires and that is way too low. The tires that come with the car are rated at 44 psi. If you keep the tires that low they wear out quicker and it kills your gas mileage. I replace the tires and the tire shop could not re-set the pressure sensors so the warning light stays on even though the tires have the proper pressure. Just one more thing that is wrong with these cars. If you are in the market for a Ford Fusion, do yourself a favor and buy a different car. Don't waste your money.