Originally Posted by Modshack

Nissan does not warranty tires. Read you warranty booklet. There is a 90% chance you have a nail in it with the resulting slow leak. This is a job for a tire store, not a dealership service dept. Get the wheel off the ground, rotate and inspect carefully if you want to check it yourself.

BTW, Anytime I've ever gotten a TPMS warning the above situation has been the reason..