This is always a safety concern. It could mean that at least one of your tires could be below the recommended inflation pressure. The first thing to do is to pull over in a safe place and check your tire pressure (all four tires). Take into account the BMW’s recommended pressure level (usually displayed on the door pillar, or sometimes on the door itself). If you are uncomfortable doing this, at least have a visual check to make sure a tire is not flat, then slowly drive to the nearest tire center to have your tires checked by a tire technician.   Fill your tires with the recommended tire pressure or, if your tires are damaged, have them replaced or repaired. The tire pressure light should automatically turn off when the tires have been inflated to their recommended pressure, and the tire monitoring system has been reset (read your BMW owner`s manual about how to reset the tire monitoring system). Please note: Not all BMW tires are equipped with TPMS sensors (they measure the tire pressure) – which are part of the tire valves.   The other type of BMW tire pressure system doesn’t have tire pressure sensors, instead, it uses ABS sensors, which read the RPM of each wheel. If the system reads that one wheel has a higher RPM, the tire pressure warning light comes on. This means that the tire is losing air, and will have a smaller radius from the center of the wheel to the ground, which causes that wheel to spin faster.