At least once a month or every check tire pressure before a long trip, including the spare tire. Check the tire pressure when tires are under cold state, which should be parking at least three hours after the inspection. If necessary, the tire pressure should be added to the pressure specified on the car sign. Because of the cold tire most accurate readings, you should drive to the nearest possible point inflatable inflated. Hot tire deflated or reduced ban. Since tires after driving warming, it is normal to be higher than the recommended cold tire inflation pressure. If you reduce the heat tires tire pressure, tire pressure after cooling is not enough. In addition, the use of high-quality gauge to check tire pressure, do not get too believe their eyes. You can not judge from the appearance of the tire inflation pressure is correct.