My tpm warning light continues to come on for no apparent reason. this has happened from day one. the elevation and outside temperature have no bearing on whether or not the light functions properly. i have nitrogen filled tires. the dealer ship says they can't find anything wrong with the system and don't bring the truck back. this is a new 2013 titan. the dealer ship said it was a nissan problem. i am constantly pulling over to check my tire air pressure. this makes long trips difficult and scares my wife when ever she drives it. nissan says to take it back to the dealer. *tr