I was driving and suddenly the (exclamation mark) turns on.. It says that I need to stop carefully. Tire Pressure Loss / Flat Tire. When I got home, I checked the tires, no flats..there's the RTS system I dont understand - Visitor
The most commonly used system will alert if one of the tire's pressure will exceed 10% compared to the others. i.e. 3 tires has 30 psi pressure and the 4th drops below 27 psi.
You won't see the tires being flat at this amount of pressure loss, but the TPMS will picks it up. When you correct the pressures in all the tires, you need to test drive your car. BMW will check the pressure at different speeds and if all good the warning will go off.
I forgot to add one more thing. If you don't have run flat tires, and have a full size spare , make sure to check the pressure in that wheel also. - ZeeTech
Thanks...I read something about checking the tires "cold". How long should I wait til I drive the car again to go to a gas station and fill up with air? Also, do you recommend doing the max 33 psi? I dont have RFT but I will make sure I check the spare too. Thanks so much. I guess nothing to worry about but just filling it with air huh? - Visitor
There is a sticker on one of the door frame or inside the fuel cap cover with the recommended pressures. If one of the tire has low pressure it must have a leak somewhere, so I'd get it checked. Most tire shop has nitrogen so you can ask them to put that on your tires. It resist temperature changes a lot better.
Zee - ZeeTech