Tire Pressure Dash Light Is Irritating Me

[Gebo]

I replaced all 5 TPMS sensors with Denso sensors about 1000 miles ago. Every tire (including spare) inflated to 35 lbs. Tire Pressure light came on once again. This is the 3rd time since replacing the sensors. I checked every tire, including spare and all are
at 35 lbs in my garage. Why in the world did this happen?

Just thinking and I have a theory. This past week it got down to 6 degrees. My wife drives to work and it stays outside where the temp got up to 20 degrees. Then after work the car gets parked in the garage with around a 40 degree temp overnight.
Could all this temp fluctuation confuse my car's computer causing it to think my tire pressure is all over the board?

 

[dadto2]

I would say that the pressure is all over the board... Does she notice the alert mostly after work, then it turns off after a few miles of driving? (After the tires heat up some?) Make sure they are fill to 35lbs cold in the driveway, see if that helps.

 

[tiger862]

Temp fluctuations or a bad tire gauge. I went thru this with new vehicle as overnight temp dropped below freezing. I checked with backup gauge and tires pressure was all over the place then reset pressure with that gauge and never seen light in months even with temp drops.

 

[Diesel12]

I gave up on my 08 Avenger and placed a piece of electrical tape over the light on dash. Solved it for me

 

[double vanos]

I think it's for every 10 degrees change the pressure changes 1 pound (up or down) . Altitude changes tire pressure too. Just driving from Sierra Vista Az (4000 ft elevation) to my house at 5600 ft will inflate potato chip bags like a football.

 

[supton]

That's weird, I don't adjust pressures often, sometimes not for a couple of months. No issues.

Then again we're used to ignoring the light for the 4-6 months of the year that we have snow tires on too. I think I have one of those stupid systems too, as long as the pressure is above say 26psi it's happy. I wonder if a smarter system might have more issues.

Can you read each sensor's output and find out what it's transmitting to the car? Maybe it's not agreeing with your gauge, or maybe one sensor has decided to only work occasionally.

 

[tcp71]

The dash light can come on for low pressure OR transmitter failure. I had one that would stop transmitting in cold temperatures as it got older and the battery wore down. Temperature came up again and the light would turn off. I have turned the system completely off in my 2016 as my winter tires don't have sensors and the light flashes every time you start the truck.

Your temperature fluctuations haven't been enough to trigger a true low pressure warning, as your gauge checks are showing. If the required setting is 35psi via the door sticker, the TPMS system won't trigger until you drop 20% or more from that value (28psi or so). Since you aren't actually seeing that pressure while manually checking, I would suspect a weak battery in a sensor(s) that doesn't have enough juice to be picked up when it's cold out. Even "new" sensors have a limited shelf life on their battery.

 

[EdwardC]

In my experience, there's usually two TPMS indicator lights, one is the tire cross section with the exclamation point, the other has the letters "TPMS". The first indicates that it detected a low tire pressure, the second that there's an issue with TPMS system itself (as if the receivers aren't getting data).

I don't know for sure, but it seems reasonable to me that maybe due to the temperature fluctuations, it could sense a fairly rapid decrease in pressure, and it is throwing a warning due to that.

 

[BJD78]

Any temp below about 15 degrees will cause the TPMS on our Forester to light up, Once temp gets to about 18 and above the light goes out. On our 2009 Sonata the TPMS light has never been triggered even at well below 0 temps. Maybe the TPMS type in Sonata wheels just handles cold temps better than the Subaru TPMs. TPMS lights coming on is fairly common in cold temps.

 

[CT8]

Electrical tape

 

[Virtus_Probi]

I never had a TPMS light because of temperature changes.
Usually they were caused by the spare being low.
Lately, mine is on all the time because I have dedicated winter wheels and do the swap myself with no appropriate tool to do the reset...I asked to have it reset when my car was inspected and even that shop didn't have the proper tool. The tire shop I like will do it for free, but I rarely head that way anymore if I am not buying tires...stupid Subie dealer wants $50, what a joke!

 

[Gebo]

Originally Posted by EdwardC
In my experience, there's usually two TPMS indicator lights, one is the tire cross section with the exclamation point, the other has the letters "TPMS". The first indicates that it detected a low tire pressure, the second that there's an issue with TPMS system itself (as if the receivers aren't getting data).

I don't know for sure, but it seems reasonable to me that maybe due to the temperature fluctuations, it could sense a fairly rapid decrease in pressure, and it is throwing a warning due to that.



This light is of the cross section of the tire with the exclamation point.

I think I'll reread the owner's manual.

 

[Driz]

Originally Posted by CT8
Electrical tape



Sometimes the simplest ideas really are the best🤗. Those things are nothing but a menace !

 

[andyd]

A 3.5 psi under 35 psi with set the light on the Camrys. A cold over night would set it. I over inflated to nearer 40 psi. So far so good. Other than oil changes this has been the only maint.

 

[Kawiguy454]

...add a few PSI and fogeddaboudit. There's no bonus points for having the pressure exactly what the door sticker says and also having the ID10T light make you crazy. Especially when we know the TPMS sending units have such sloppy sensing specs.

 

[JTK]

Sorry if I missed it, but does the vehicle show tire pressures or just the lights?

Like EdwardC said above, there's typically the two separate indicator lights. The one you have (tire cross section with !) and the TPMS light which typically lights when the system itself is having problems with either the transponders in the tires or the receiver(s) on the vehicle.

I too would try airing the tires up to closer to 40psig and see if the light goes out. Like said, the TPMS have a +/- 3psig or so deadband you have to clear for the warning to clear.

 

[sloinker]

I despise in the tire TPMS sensors. I heartily approve of the style VW and others use that measures a couple different parameters to determine if you have a low tire. Easily reset-able through the on board menu.

 

[eljefino]

You're lucky in that it's a toyota product for which you can get an economical Techstream dongle on ebay which gets you diagnostic abilities.

Do you have a button for it under the dash? This sets the "now" PSI and the light will only come on at 20% under this.

Techstream reads for me, and maybe for you, if the sensors have low batteries. Since you bought new recently, this is unlikely but not impossible.

You'll notice I have one bad/missing sensor giving no data, and a couple with low batteries:

 

[Linctex]

I put a piece of black tape over my tire pressure light.

Nothing I ever did would stop it from coming on.

 

[HangFire]

Originally Posted by Gebo
Originally Posted by EdwardC
In my experience, there's usually two TPMS indicator lights, one is the tire cross section with the exclamation point, the other has the letters "TPMS". The first indicates that it detected a low tire pressure, the second that there's an issue with TPMS system itself (as if the receivers aren't getting data).

I don't know for sure, but it seems reasonable to me that maybe due to the temperature fluctuations, it could sense a fairly rapid decrease in pressure, and it is throwing a warning due to that.


This light is of the cross section of the tire with the exclamation point.

I think I'll reread the owner's manual.

I had that same light on my Honda when my then-12 year old TPMS batteries started dying. I bought 4 new Schraders on Amazon for $35/ea and when I bought new tires, had the tire shop replace all of them. Still had the light after that. Bounced tires, one had a rattle. Tire shop broke one of the Amazon TPMS sensors, they put on a new one for free, but had already warned me they couldn't program any of them. (Honda Pilot is supposed to be self-syncing.)

I tried the deflation test, and got only two low pressure indicators on one side, none on the other. The Low Pressure indicator was a different indicator than the one your describe, showing me which tire(s) was low.

After almost a year of futzing around with wheel rotations, resetting the TPMS computer, etc., I took it to my trusted local mechanic and for a little over $120 he replaced the two bad sensors on one side, programmed them and gave me back the broken ones. It was crazy how fast he diagnosed and fixed it.

I returned the broken ones on Amazon and got my $70 back, almost a year later.

So in the end I still saved money, but next time I know who I'm going straight to for new TPMS sensor installation and programming.