The stupid TPS light came on this morning on the way to work. Kind of freeked me. I kept my speed down and made it to work. One of the other guys had a cheap pressure gage and all four read above 30 psi after a 3 hr. cool down. They weren't even warm when I got to work. So, what's wrong ? The sensors are the originals that came with the car.

 

Probably got old and one of them probably died. Take it to a dealer and ask if they can check them all out.
They'll probably quote you at over $120 just for one, so I would say buy a used set off the marketplace for the same cost and you'll get three spares.

 

You are a couple psi low.

Add some air and see if light goes away

 

I have a calibrated pressure gage at home. I'll check and adjust tonight.
I know the sensors run on batteries. Can they be replaced?

 

No. Entire sensor would need to be replaced.

Is the light on solid as soon as you turn the car on? Or does it blink for a while and then turn solid?

 

The light started blinking first, then stayed on solid after 10-12 minutes from the house this morning. I haven't resatrted yet.

 

Your spare tire might be low too.

 

The spare doesn't have a sensor and is not in the system.

 

Is that possible? My light come on ocassionally on longer drives, there's no alarm like when a tire is low and the tire are all fully inflated.

 

on the first Gen G35s at least, if the light turns but there is no alarm then there's a problem with the system - bad sensor, communication error, etc. have the stealership check it out for you.
i get the same thing on long drives too - my tpms light will turn on after 40-50 miles on the highway. mine is due to the EMF thrown off by some of my electronic gauges which apparently interferes with the signal between the sensors and the control unit. the system still works though (an actual flat will still produce an alarm).

 

I do have them come on long runs too, especially on my summer wheels.

 

Mine's pretty much the same, it work's, low tire pressure produces an alarm and a flashing light that stays on after a key cycle. On long drives the light will come on with no alarm and turn off after restarting the car. Dealership says it all works fine, they ask me to bring it back with the light on which I did, the first thing the dumb *** did was turn the car off and the light went bye bye. It's not really worth wasting any time on but I will check the air pressure in my spare.

 

This morning I pumed the tires to 34psi by my calibrated gage. The light stayed on. I turned it of with a tool that plugs into the computer connection under the dash. I don't have time today to see if it stays off.

 

Is this a problem on these cars? My wife drives on '05 that we've had since new, and it's been a chronic problem. If you drive it far enough, the light will come on. I've reset it, but that accomplished nothing. Is there a fuse that will disable the entire system and keep the light off? Any other way to accomplish the same task?

Mark

 

These sensor run on batteries and they will die out sooner or later.

There are cheaper TPMS sensors that you can buy for around $100 for a set of four.
Buy them and let the car run the way it was meant to rather than disabling fuses etc.
It is a safety feature and works fine if you correct the problem.

This is not a problem on these cars as im sure there are other vehicles out there that use tpms sensors with batteries in them.