I've been having a tire losing pressure and my light has been coming on and I've put air in it and the light goes off.

Well yesterday, my light came on 24 hours after I had put air in the tire and I checked the tires and they were all fine.

How does the sensor work? Does it compare all 4 pressures and if one is low compared to the others it throws the light or are they set so that if the pressure reaches a certain level, it comes on?

I run 38-40psi in all my tires so I'm wondering if that's what's causing the issue.

They read the pressure of the individual tire and compare it to the preset limit. If you have a full size spare check it, they also have sensors and can trip the light.

Your tire pressure sensors are set at 29 lbs when any tire drops below that you'll get the warning on your dash. I suggest you stop into your favorite tire store and have them check out your tires. Any time I get the warning I always run into my tire shop and it's always been a nail I picked up....Gary

The light came on and I checked all the tires and they were fine... That's why I think it's a sensor issue...

I don't think I have a full size spare as I have the OEM Rays.

Do the sensors trip with over inflating also? Maybe your 38-40psi is too high.

Door jam sticker says OEM 19" rays are 35psi all around. I do 36psi no problem.

Oh and make sure measurements are cold... like first thing in the morning ideally.

check the spare tire and sometims they are very sensitive

I was wondering the same thing. I'll lower them down to 35psi tonight.

Do the coupes with the OEM Rays have a full size spare with TPMS in the trunk? I haven't ever looking at it lol

The tire pressure you're running has no effect on your TPS, I always run 37 lbs. Like I posted the warning only goes off when I pick up a nail and drop below 29 lbs. You could remove your spare and it wouldn't have any effect, check your tire pressure one more time....Gary

full size spare tpms will not transfer pressure to car's monitor system unless it's on the car & rotating.

i took em out and chucked em..

every time I would drive through mountains they would falsely trip

just check em the old fashioned way

I stand corrected, read the owner's manual and you are right.

Is the TPMS beeping when it comes on? Or just the light.

When my tires are low the light will come on with a long, 8-10 beep from the dash. The light will not reset until it detects proper tire pressure @ ~20mph or more.

Sometimes the light comes on after driving 60-75 miles with no beep, and turns off at next restart. No idea why but it isn't enough of an issue to have checked out.

Which is yours doing?

DGrantG, if all your tires show you have the correct tire pressure and you're still getting the TPS warning I'd take your G into Nissan and find out why. That's what I'd do....Gary

how old are your tpms senors? may be tpms sensors batteries are about to go out completely.

Mine does that as well. No idea why either.