Put in air when the tires are cold, maybe use a portable home pump, so you don't even have to drive to the gas station, if the station is far. Then reset the Tire Pressure Monitor (TPM), it should stop showing the warning.

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2008 E70 X5 3.0si
Sport | Prem | Adaptive Drive | Tech. | Cold Wthr | Rear Climate | 3rd Row | Running Boards | iPod/USB

2019 G30 530e
Sport | Adaptive | Drv. Assist+ | HK | HOV Access

2018 F83 M4
Comp. | Exec | DCT | First M Car

2009 E93 335i (Sold)
Sport | Prem | 19" 230 | Logic 7 | iPod/USB | Sat | HD Radio | Comfort Access | Heated Seats | Pure Joy

E36 328is GoKart (Sold)
Manual | HK | Trip Comp. | 17" Rims