My tire pressure went off when the temp dropped last week, checked tires all is fine, any way to re-set without going to the dealer?

 

I don't know if you resolved this problem yet but if anyone else has it, you need to drive at least 25 miles for the transmitter to start sending. For some reason Nissan decided that 25 miles was what it would take for it to start sending every minute. The other way is to just leave the car running for about an hour. This won't fix all problems with the transmitter but may solve this one. This is documented in the 350Z shop manual.