"5/14 April 7, 2005. All U.S. passenger cars will have tire pressure monitoring systems beginning with the 2006 model year according to a new safety rule by NHTSA that requires a system to detect a tire 25% under recommended pressure. Phase-in begins 9/1/05, and all vehicles under 10,000 pounds must be equipped with it by the 2008 my. "
Source:
www.cars101.com