Mr. Toad

Which is more accurate, the tire pressure indicator in the instrument cluster, or an inline tire pressure gauge? Mine disagree and I'm wondering which I should trust.

Mr. Toad

BUMP

Isawelvis

I have noticed the same thing too but normally only 1 or 2 lbs difference. If you drop your tire gauge, it could damage it and cause a faulty reading. Buy another tire gauge and get a quality one and see how it compares. Alot of people just use the cheap plastic tube type, I would invest in a metal tube type or one with the round dial. Good luck.

Mr. Toad

I have two gauges - a round, dial-with-needle type and a brass tube one. They both tend to indicate a 2-3 pounds more than the dashboard readout.

Dutch2

I think I didn't make myself clear.

The sticker says 33 psi.

The low pressure warning on the display says a tire that is 40 psi is OK, and that a tire that is 37 psi is low!

I used a gauge to measure the tire pressure and the tires are close to the pressures displayed on the warning screen.

D.

whoover

It's responding to the difference between pressures on one axle. Just set all tire pressures to where you want them with your gauge and restart TPMS. To be safe, set them all to 33 as per the sticker, restart TPMS, and then change the pressures to what you want.

Dutch2

How is 39 psi OK and 37 psi is not if the recommended pressure is 33 psi?

whoover

I believe it's calling your attention to the fact that you have a 2 PSI imbalance at your rear axle. That's an easy enough theory to test.

Isawelvis

There is a way to reset the values ie adjust the desired airpressue you want to maintain in the tire. If you wanted to you could make them all 39 PSI and it would be the base setting. I just google this and found out how to do it.

Dutch2

I think I have it figured out...

It has nothing to do with an imbalance in pressures or anything like that.

The car simply records the tire pressures when you reset the system. When the pressure is 3 psi below the pressure you told the system is "normal", the warning pops up.

The driver side door jamb sticker says 42 psi, I believe this is the maximum pressure. Whoever checked the tires (at the dealership!) must have though that was the normal pressure, filled the tires to 42 psi, and reset the system. That is why a 40 psi tire was OK and a 39 psi one was not.

I let some air out of the tires until they were all 33.5 psi and reset the system. All is well.

D.