Tire Pressure Monitor light came on

[jetfuel]

...I had the light come on on our way to the Dragon run....pressures were OK...reset will extinguish the light verifying the system has accepted the current pressure as reference...few miles down the road light back on...it turned into a fight to see if I can turn it off as soon as it came on....took it to the dealer for service the following Monday...the tech said that it did not flashed any malfunction code and that the tires were low and they serviced them....I requested to bring the gauge and show me the pressure setting they set the tires to...fronts were set at 32 and rears at 41..I asked to be set to sticker values....after they were done I used my gauge to see how it compared to the center's unit...my gauge was within a pound of theirs...
...the light has not come on since,,,what the heck did they do?...don't know...
sorry for the long rant...

jetfuel..."in God I trust everybody else I check"

[SmartDigger]

Mine came on the other day. First cold day here. All 4 tires were exaxtly 5 pounds low. filled up tires and all has been well since.

[fpage77]

Mine came on the first time and I filled my tires and less than a week later came on again and found a nail in my sidewall. I got another tire and the thing only came on once since (normal pressure loss over time) and filled the tires and hasn't come on since. I'd watch the warning of the system and check your pressure and fill again and if it comes back on again a few days one of your tires probably picked up a hitch hiker.

[dlomshek]

Last week I also had the tire pressure come on and I found the left
front tire 2-3 lbs. low. It's been much cooler here since I bought
my baby on July 14. I aired up all tires to specs and no more light.

Dave Lomshek

[eskargo]

mine came on last week.... aired up all tires. light came on again the next day. left out in garage and driver rear tire was flat. found screw in one of the threads. inflated tire and drove to dealer and they took care of it for me.

[fortow]

Originally Posted by Padawan

Also keep in mind that any time you inflate the tires to proper pressures, you also want to recalibrate the TPMS system to recognise those pressures as the correct baseline. This is done by simply pressing the TMPS button on the button bank until you see the warning indicator on the gauges cluster flash.

If the system was already calibrated to accept the standard OEM pressures then there's no need to recalibrate it after reinflating the tires back to the proper pressure.

Test this out- remove air in one tire and you will note that the driver's information display then shows the tire symbol with the exclamation mark. Not simply re-inflate the tire to the proper pressure and that tire symbol in the left hand space of the display will no longer be there.

You only recalibrate the TPMS system when you want to change the calibration pressures.

[chobocobo]

Thanks guys for the advice. I think I'm just going to buy a cheap tire guage from like autozone since the emergency kit isnt fun to get out.

[Chris Wurgler]

Don't go too cheap on the cheap gauge!
Go Digital if you can.
Some of those pencil gauges tain't worth a d*#!

[jvc777]

I filled my tires w/nitrogen ( go to www.getnitrogen.com), and have had the tmps come on twice now. The nitrogen is supposed to stop the slow leak of air thru the rubber due to the larger nitrogen atoms = less leakage in cooler weather. So far not impressed with the nitrogen staying power but it does ride a hair better, remember nitrogen gas shocks. Anyway the psi drops in all 4 tires, may be due to the aluminum wheels flexing Anyone care to comment? JC

[Brabus007]

~Seeing as were talking about AIR~We Best AIR This Subject OUT~

~Don't Be The Fool~Don't let them laugh at YOU all the way to the BanK~
NOTE: If you do top off your tires regularly, and it is the oxygen leaking out, with the nitrogen not leaking out as fast, what is left in your tire after many months? I would think it would be mostly the nitrogen.

Nitrogen is probably another example of an industry trying to make more money by selling you something you just do not need. Using dry nitrogen in your tires would mean that the 21% of air that is oxygen and a tiny bit that is water vapor will not be inside your tire, but remember that ordinary air is 78% nitrogen to start with. There are a number of claims of improvements due to using nitrogen...

One claim is that nitrogen reduces oxidation of the rims and the rubber as there is no oxygen or water inside the tire. Nice claim, makes sense on the surface. But I have never seen any signs of oxidation in my rims even on my currently 12 year old vehicle, never had a tire fail due to deterioration of the rubber or even heard of such a thing. A tire is likely to wear out long before rubber deterioration becomes an issue, if it was the tire companies would be getting sued left and right due to failing tires.

Another claim is that tire pressure changes less due to temperature. As long as all of the components remain a gas there is no difference in the temperature/pressure performance of pure nitrogen versus air, you get about 1psi for every 10°F change in temperature. The claim is that when the water condenses it will reduce the tire pressure. In the higher pressure inside the tire the temperature that water will condense is much lower than the same air outside the tire. It is unlikely that this is a major problem.

The one claim that seems to be something to consider it that nitrogen permeates (leaks) through the rubber more slowly than oxygen meaning that the tire will loose pressure at a lower rate than a tire filled with only air (You Still Lose Nitrogen At A Little Slower Rate). Claims are 1-4psi per month less loss meaning you will get better fuel efficiency and lower tire wear due to low pressure tires. This is easily dealt with by simply checking tire pressure regularly.

Another interesting thought... If you do top off your tires regularly, and it is the oxygen leaking out, with the nitrogen not leaking out as fast, what is left in your tire after many months? I would think it would be mostly the nitrogen.

There are some places where nitrogen is used regularly...

Racing teams generally use nitrogen to fill tires. But these teams also tune the cars to a very fine degree to shave fractions of a second off a race. Drivers claim to see handling differences with very small tire pressure changes (not being a race car driver myself this seems odd). So getting the water vapor out of the tire might make a difference in handling. These are changes that will just not be noticed in a non-performance vehicle like your SUV or minivan.

Aircraft tires are routinely filled with nitrogen, but then consider the conditions aircraft tires are subjected to. They sit on hot asphalt, with temperatures of well over 120F and a few minutes later they are at 30,000ft where the temperature might be -40F. When this cycle is reversed they are expected to survive many tons of aicraft hitting the ground. Frozen water in the tire could be a bad thing, it could freeze on one side of the tire while in flight then create an off balance tire when the aircraft lands. Just a little more extreme environment than your average passenger automobile.

Handling nitrogen is easier on an airport flightline where personnel can be trained in it’s safe use, it is usually stored in liquid form which can be dangerous to the novice. Nitrogen is already available on the flightline as it is needed anyway for pressurizing aircraft struts and hydraulic systems.

So for automotive uses you should save your money, use plain old air, and remember to check your tire pressure more regularly.