2010 Prius: It would be nice if TPMS would display the tire pressure, however, is seems that there is 1-bit (on / off) LED indicator. Obviously if the light is on, then tire pressure should be checked. Questions: 1) What is the tire pressure range for the LED to NOT light up? * 2) Is it possible to readout the tire pressure from ODB or the like? * Any reference would be appreciated.
Yes, with a capable OBD-II scan tool you can see the pressure and temperature in each tire, and also the threshold pressures below which the light will come on. You don't get to set the threshold pressures directly. What you do is inflate the tires to pressures you want, then use the SET button, and each tire's alarm threshold gets set to a certain percentage below its current reading. Something like 25% below—a lower threshold than you might expect. I fudge around that by overinflating the tires before using the SET button, then letting them back down to the real pressures I want. That way I get the alert a bit earlier.
