TPMS sensor kaput?
 

My 2008 RAV4 had an unfortunate encounter with a pothole. The rims were not damaged and all of the tire pressures are correct, including the spare. But the low tire warning light is now stuck on and flashing. I'm assuming one of the tire sensors was damaged by the shock. The question is which one is bad and what do you do to fix it. Are they coded to the car? Is this a dealer-only fix?