A while back, I contributed to a project in which we wrote a program that would allow you to hook up your laptop to the car's onboard computer (we used a cable with a build in converter from the OBD spec to serial). It would read (and clear, if you wanted) the car's trouble codes, and process a whole bunch of metrics based on the data that the on board computer throws. I assume the most commercially useful aspect of this would be to allow you to make a car shutup about not wearing your seatbelt
I wrote a series of (XML) files and internal programming objects to represent the trouble codes themselves, and I couldn't seem to recall anything in OBD-II having to do with "low tire pressure". As it turns out, there aren't any codes in the current standard - all the standard has is codes for the "Tire Pressure Monitoring System" not communicating with the on board computer - essentially meaning that the tire pressure system itself was on the fritz, as far as OBDII is concerned. Since OBDII was first incorporated/standardized in the late 90's, this means that tire pressure monitoring was a completely after market deal and apparently remains so, at least for the time being.
I don't think that really has any bearing on anything Obama said, but I thought some might find that interesting.
Here are the OBDII trouble codes, for anyone interested:
Generic OBD-II C Chassis Trouble Codes (with tire interaction)
Generic OBD BXXXX Body Trouble Codes (generic "catch-all")