ttran1130

After riding around on aftermarket wheels, I decided to put back on the factory wheels. Keep in mind that I did not have sensors on the aftermarket wheels. So after putting the factory wheels back on the TPMS light did not turn off and the pressure isnt showing on the info panel. Do I have to get the sensors reprogrammed? Maybe it needs some time to pick up signals? Any advice is appreciated, thanks.

AL13NV8D3R

I am not so sure but there should be a tire pressure reset button somewhere on the car maby under the steering wheel where the gas pedal is located. This is a great time to refer to your Lexus owners manual.

bclexus

Correct. OP will have to get his head down low (near floor mat) and look upward under the dash to see the TPMS reset button.

mickey1529

I have a 07 RX 350 , 91 k, TPMS warning light came on. I took it to a shop and a sensor was bad and they replaced and when I picked up the car the lihght was out, 1 week later the light is on again. I went back to the shop again , all tires and the spare are at 30.5 and the light will not reset. All 5 sensors read and went to the board but it still will not reset or go out. Does this mean I might have a bad board? any suggestions would be helpful, it is set on 1 set of tires. Thank you
2007 RX 350
2007 F150 FX4

Atomic350F

Per the manual page 413,

First make sure you have the proper tire pressure all around, while your tires are cold.
Then turn the engine on.
Then hit the reset switch and hold it until you see the tire pressure warning light blink slowly three times.
Leave the engine on a few minutes, then you can turn it off.

It shows a diagram of where the switch is located, looks like its under the steering column on the lower dash panel, but I couldn't actually find it in my car!

Hope this helps..

ttran1130

Thanks atomic got the sensors to read. Now I got another question, the closest dealership that has nitrogen is about 45 mins away. Can I just add regular air on top of nitrogen? Good or bad idea?

bclexus

If you need to add pressure to your nitrogen-filled tires by using regular compressed air - it isn't a problem. Air is 78% nitrogen anyway. By topping off a nitrogen-filled tire with air you are only decreasing the effectiveness of the nitrogen in your tires.

Joe166

What exactly is this effectiveness of nitrogen? As you noted, air is mostly nitrogen anyway. If you google nitrogen in tires you will see mostly skeptical reports, some citing a Consumer Reports study from a few years ago that tested most claims, particularly that since nitrogen molecules are slightly larger than oxygen molecules they would obviously be less likely to leak out and lower tire pressures. They found the differences to be minimal.

Logic also rears its ugly head. Since no dealers I am aware of have hyperbaric nitrogen chambers (or whatever that might be called), tires are already full of air when mounted and inflated so no tires are really 100% nitrogen filled AND if it is true that the oxygen leaks out faster, then each time you top off your tires you are increasing the percentage of nitrogen in your tires.

Nitrogen makes sense in aircraft and larger tires such as trucks but in passenger cars it is just a gimmick to separate dealers with good PR (if free or cheap) or a profit center. You would spend your money far more wisely by buying a really good tire gauge or just monitoring the tire pressure to avoid underinflation. That is just my opinion and I could be wrong, but if I am, so are lots of other people.

kmm

My understanding is that nitrogen is less sensitive to temperature changes-found in areas with big temperature swings like Las Vegas or Palm Springs.

I think all Costco stores fill with nitrogen.

Joe166

Isn't the tire temperature more affected by things other than ambient air temperature? Like underinflation, or overloading? I live in Florida and my 78% nitrogen filled tires go up about 2 or 3 psi when driven at 70-80 mph for long stretches. Would 95% nitrogen minimize that? Should I care? If someone wants to put nitrogen in my tires for free, go at it! If they want money for that, I'll pass, thank you.

I guess when people stopped buying undercoating and $300 polymer "wax" jobs, they had to come up with something to fatten the bottom line. In my opinion, a far better investment for people would be a decent tire gauge...and using it once in a while. Or keeping an eye on our dashboard.