Tire PSI (Non)Warning Light

[SPF 0]

I had never checked the tire pressure, figuring the dealership would do that at oil changes and the "tire low" light would alert me to low pressure.

Checking them manually yesterday, I found them off by anywhere from 10-<i>25</i> pounds. I brought them all up to spec and hit the pressure "reset" button. It seems I was far more reliant on the light than was prudent.

I figured from this lesson that if I can't serve as an example to be emulated, perhaps I can at least serve as a warning to others.

[MrMikeL]

Bells & whisltes can never replace the basics. For example, I calculate my MPG each time I fill up rather than depending on the computer. That tire pressure light is nothing more than a nuisance, since there are way too many false positives.

[theprodigy79]

Bells & whisltes can never replace the basics. For example, I calculate my MPG each time I fill up rather than depending on the computer. That tire pressure light is nothing more than a nuisance, since there are way too many false positives.

Agreed. The computer functions are nothing more than simple conveniences that give you estimates... I use them to monitor my driving styles, and to compare different tanks, but nothing more really than that (I don't rely upon the computer to tell me exact figures, otherwise I wouldn't push it 15-20 miles beyond when it says I have 0 miles left...)

As far as the low tire pressure warning system goes; I would not just reset it, I would completely recalibrate it if it was that far off... It is intended to show large deviations between tires, and won't usually pick up on small things until they become larger issues, however if your tires had those types of deviations it sounds like your system wasn't properly calibrated to start with. If you don't want to do it, or you don't have any open roads where you know you can maintain speed, your local dealer should do it for free (it takes around 20 minutes).

Also note that the system DOES NOT know the actual pressure of each individual tire (or any pressure levels at all for that matter). Once it is programmed properly, it uses calculations for time and variance to determine if one (or more) wheels are spinning at different rates than what it was programmed for (in comparison to the other wheels). If it is programmed incorrectly, it won't catch the variance (or it will "think" it's normal) and won't warn about it. Even if it IS correctly programmed, there are still situations (albiet rare ones) that it won't work properly (for example, if all of your tires were to lose pressure at an approximately equal rate, the wheels would still spin at the same rate as each other to maintain the designated speed, and therefor it wouldn't read as an error).

Let the dealer know what happened, then have them inflate / deflate as necessary and make the programming correction. Another way to determine if your Tire Pressure Warning System is not programmed correctly is if the light stays on for more than a second (I believe) after the other warning diagnostic lights go off. You may want to look that up though...

Good luck with that,

-James

[TW85]

Do you have the stock Bridgestone Turanzas? They tend to lose air and require checking more frequently than most tires. Reason number 174 to replace the Turanzas!

[Jackass-Jeff]

The tire pressure sensor works by measuring deviation of tire pressure, not a set amount.

Let's say suggested is 32 (I don't know Gen 2 PSI). It will read 32 PSI as 0 and will allow +/- 5 PSI (I don't know the exact spec)

If the system is ever reset w/o adjustments, then the reset will assume the new PSI to be "0".

Therefore, we can assume your dealer doesn't check tire pressure and just resets the system =x Or the sensors are bad (have dealer test them as a warranty concern at your next service).

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MPG display: It's nice to have, but is almost useless... lol It may be reading as 30+ but you're only getting (iono) 28 or so. =P I think that's just calculated by: fuel pressure ECM output voltage and traveling speed.

[jsie]

My tire pressure warning system works like a champ! I do inflate all four tires to 35 psi. About a week ago my warning system lights up, I checked all the tires; it turns out one of them had a nail & lost about 5 psi (30 psi reading). I had the tire fixed and re-inflated to 35 psi, reset the warning light, and everything works back to normal. I really happy with the system; it gave me an early warning before the pressure lost become noticeable, or to the point that may damage the tire due to low pressure.

[SPF 0]

Its turn out for whatever reason the car was delivered with the tire pressure warning system shut off.

A trip to the service department got it fixed right away.

I'm looking forward to sharing your happy experience with the monitor!