During the past several months there have been several threads regarding TPMS. There have been questions regarding whether or not 2012 sensors would work on older models. Some have said Chrysler changed the frequency. Others have said that they had to be programmed by the dealer.
I have been dealing with a faulty TPMS for the past year and a half. When the TPMS is not functioning properly, the light will flash for 75 seconds and the remain solidly on. According to the owner's manual, several things can interfere with the radio signal, including window tint.
I learned the hard way why this system is ill suited for an off road vehicle. The wheel sensors each have batteries that cannot be replaced. Constant airing down causes premature failure of the batteries, hence my warning light has been on.
I bought a brand new set of 2012 Rubicon takeoffs last year and have been patiently waiting for my current set to wear out. I decided to put the new set on today. These tires have been in my basement for a year and surprising they all held their air. I had to let a little out of one and top another off, but they were surprisingly close.
I went for a drive this evening and as usual my TPMS light flashed and remained on. No more than 2 miles later the light went out and stayed out. The 2012 sensors are completely compatible with my 2009 X.