ZaKapitan

let me clear a couple of things up:

First of all, there are two buttons under the steering wheel, right by your right knee. That's right. one is to reset the tire pressure guage, that's also correct. the other one is not to disable trac, it's to disable the headlights from moving as you take a turn.

Secondly, there's a button in the same place, on the passenger side. This button is a toggle switch, and is used to set two different sets of tire sensors, in case you have two sets of tires you regularly change out. The default is set to 1, and that's the set of tire that came with your car. If that switch is set to 2, you may also get the tire pressure light.

wanderer99

Has anyone actually worked out at what point the light will come on? I set all my tires at 30 PSI as recommended and find the ride is smoothest at that level.

From delivery I had as high as 37 PSI and as low as 29 (I think) and the ride was harsh. I set all to 30 PSI manually and the ride is great. Tire pressure light did not go off.

We noticed the other day that the ride was different, and the tires varied from 29\27\28\26 PSI. Again, the low tire pressure light was not lit. I've got a feeling it must be a pretty dramatic change (like 10 PSI or something) for the light to go off.

LexBob2

That's a good point. Our car was delived with 40 psi in all of the tires. The dealer reset all four of them to 32 psi and didn't have to reset the tire pressure monitor. If it takes 10 psi or more before it goes off, that seems like a lot to me. I'd want to know sooner than that. I check 'em regularly, but since the car has the monitor you'd think it would be more precise.

Swobro

Interesting thread. I had the pressure light go on about 3 weeks ago - it would light when I first started the car, then would go out after driving several miles - likely the tire heat was increasing the pressure to "back in range."

I just ensured that I had 32psi all the way around (had to add some air here and there) and after that no problems.

I really like the tire pressure sensor feature..not only will it give warning of slow (or fast) leaks, but also bring your attention to REALLY slow leakage that will influence your mileage!

ZaKapitan

the tire pressure light isn't to tell you ALL your tires are low, it's there to tell you that ONE of your tires are low. As you drive and your tires get warm, the tire pressure increases. the tire pressure guages cannot really measure PSI tire pressure, just a difference between the 5 wheels.

So deflate one tire a little bit, and it'll turn on. once it's on, it will not turn off until you get that tire, and all others, up to the pressure it was at when you reset the system with the reset button under the dash.

Neuroguy

Had my car delivered with 40 psi in all tires - seems they forgot to deflate them during the delivery check. (BTW, they over-inflate the tires during transport to prevent flat-spotting.) This was in early May. I set them to 34 psi and reset the monitor. Last week while driving to work, the tire pressure monitor light on the dash went on. Oh, **** I thought! But, the car still drove fine, so I kept on going. Got to work and checked the pressure in all tires and they were all at 30 psi. The ride is better at that pressure, and that's what's recommended, so I'm keeping it there. Reset the monitor and all is OK. So, by my experience, the monitor goes off when the pressure varies low by 4 psi.

BTW, a friend has a Saturn, and he had his go off when a tire was *over* the set pressure.

tnfan

You guys must have jinxed me! My low pressure idiot light came on yesterday evening. Checked the tire pressure this morning before I left for work. Pressure was 30 PSI all around. Did the reset thing and the light still comes on. Guess I will have to take it to the dealer to get get it reset.

tnfan

Well dumb me! I didn't think about the spare tire. Spare tire pressure was 26 psi and caused the idiot light to activiate. Set the spare tire to 30 psi and everything is back to normal. Guess I need to slow down and read all the threads. I missed the one reminding to check the spare!

2puppies

Also remember if they switch out wheels for any reason that will cause the tire pressure monitoring light to go on. I just bought my car yesterday; drove for about 30 minutes and the light went on. I went to another Lexus dealer nearby, and they said that because I had the wheels switched since I wanted the Michelin tires and not the Goodyear, that the service people had forgotten to register the codes of the different tires. So not sure how it's handled when you go to replace your tires at Sears or Discount or wherever. If Lexus service people are still learning, will the rookies at the tire shops know what to do?

They said the reason it didn't come on immediately is that the computer automatically tries to find the correct codes and keeps retrying for awhile; then it basically gives up and the idiot light goes on.

Some idiot there tried to tell me that you have to keep the tire pressure level at 35 psi even though it's posted at 30 because when you're doing highway driving it'll change. Seems to me that the psi goes up when you're doing highway driving, not down? Anyone had a problem with the monitoring light going on just because you're doing highway driving?

NoiseFree

I've got the 'low tire pressure' idiot light blues, whoa mama.......
I said I've got the low tire pressure' idiot light blues, whoa mama.......

I've had my car now for 8 months and haven't had any problems.
Yesterday I brought in my car for the 6 month/8000 Km free maintenance.

Today my low tire pressure idiot light came on when I started my car and stays on.
The ride is noticeably rougher than before I brought it in for maintenance
so someone has fiddled with the tire pressure.

I've got the 'low tire pressure' idiot light blues, whoa mama.......
I said I've got the low tire pressure' idiot light blues, whoa mama.......

Can I sue anyone?
This is going to wreak havoc with my sleep tonight...

350Dave

Why do so many seem unable to spell "gauge" properly?

Seems like "guage" is more popular!

PsychDoc

I have know idear why u ewe wood say that.

Most poepple thinks that there way of spelin' is totaly korekt.

What r ewe, some kind of retarde?

amf1932

Yoore speling is atrciouiocisis.

LexBob2

I agree. I'm going outside now and clean the break dust off of my wheels.

jerfitz

TPMS & Run Flat tires. I have a friend whose TPMS failed and did not indicate that it failed. He has run flat tires. During his driving on a trip the car finally felt so funny that he stopped at a Lexus dealer. The steel bands were protruding through the left rear tire and there was ZERO air pressure in the tire.

Before stopping at the Lexus dealer he did stop one time but all the tires looked okay and felt okay when he kiched them. I guess it's tough to determine when a run flat tire actually is flat!