I have a 2008 Ford Focus SE that Supposedly has TPMS sensors and i just changed the wheels from the stock steel wheels to a set of aftermarket alloys off a 2007 focus without TPMS how long does it take to recognize the sensors are not there and turn on the light. i have put approx.45km on it since the change and no light no performance issues. the tire shop i went to said the only issue would be a light on the dash and i can live with that just want to make sure FORD didn't charge me for something they said i had but don't. THIS WOULDN'T BE THE FIRST TIME!!!!!!!!!!!!