Today i was driving on the interstate and all of a sudden my "low tire pressure" message shows up. i stop to check all the pressures and they're at 32psi. soo....i'm assuming there's a fault in one of the sensors and i'll need to replace it to shut the light off. anybody know a lot about GM tpm's?

 

You can access the menu to reset the error message through the stock radio, in case it was just a glitch that caused it to set.
Otherwise, the TPMS is based through the ABS sensors, which just detect a difference in wheel speed to determine a difference in tire pressure.
Best of luck,
-Riggs.