Basically run flats have thinker sidewalls which allow the vehicle to be supported with little to no air for a short amount of time. So, if you get a puncture and the tire goes flat, you can still drive (slowly) on the tire to get to where you are going. The reason that they put them on the car is because you have no place to put a spare tire.
As for pressure, you should always look at the panel on the inside of the door toget the correct pressure for your car. Stick to that and you will be fine. As Randall stated above, the pressure system only monitors the speed of the tire rotation. When that changes, then the will trip the light as it thinks there is a flat. The system does not monitor the actual pressure in the tire. So, it is always a good idea to make sure you check your pressure from time to time. |