So I'm reading through the Owners Guide and come across this: What strikes me is that this is almost identical to the way the TPM works in my Pontiac Vibe. The Vibe has no wheel pressure sensors and relies on the ABS system to detect a wheel spinning at a slightly different RPM compared to the others as a result of its diameter changing due to under inflation. The reason for the 10 minute drive after re-inflation is so that the system can re-calibrate itself via the ABS sensors. It has worked for me on the Vibe, but you don't know which tire is the problem until you get out and check. In my view, it's inferior to having wheel-mounted sensors, but it does work. I wondered why Model S has no display for individual tire pressures (like my Cadillac CTS does) and this may be why.