TPMS Question

[Co.Ag.2005]

I've had my '06 Limited 4Runner for a couple of months now, and I have noticed that on cold mornings (temps in the upper 40s / lower 50s), my TPMS warning light comes on when I leave my house for work. Once I have driven for about ~10-15 minutes (therefore the tires have warmed up), the light goes off.

This makes perfect sense. Cold air means the pressure is lower due the compression of air at those temps and as soon as the air in the tire warms up, it expands and is back to normal pressure.

I just want to know if this is normal for the TPMS to sense this slight fluctuation or if anyone else has seen this regularly? Thanks in advance.

 

[ran]

Yes, normal. I had the same question on my '07 Sport. I did air them up a bit more, got tired of the warnings.

 

[SubSonic]

Since you're from Colorado, I am somewhat surprised that you'd call 40º-50º mornings "cold"...lol

This does sound normal, somewhat. 40-50 is a little "warm" IMO for pressure to sag off enough to trip your TPMS, but I guess it could be. I normally don't see any cold-air pressure falloff until we get closer to freezing here...

I'd manually check them and maybe top them off closer to their factory pressure spec, as it sounds like you may be running them a little too close to the 26psi it takes to trip the system. I believe my "door tag" recommends 32psi for my 18" tires. That's good, 32psi is usually a good compromise between mileage (35+ psi) and ride quality IMO in most tires today (outside of the really low profile jobs, where you need 38-40psi or better, like my wife's new Pontiac G8)

Also, don't forget that there is also a sensor in your spare tire - so make sure it is up to the proper pressure too.

 

[ric]

mine "never" comes on anymore :

 

[Co.Ag.2005]

Since you're from Colorado, I am somewhat surprised that you'd call 40º-50º mornings "cold"...lol

This does sound normal, somewhat. 40-50 is a little "warm" IMO for pressure to sag off enough to trip your TPMS, but I guess it could be. I normally don't see any cold-air pressure falloff until we get closer to freezing here...

I'd manually check them and maybe top them off closer to their factory pressure spec, as it sounds like you may be running them a little too close to the 26psi it takes to trip the system. I believe my "door tag" recommends 32psi for my 18" tires. That's good, 32psi is usually a good compromise between mileage (35+ psi) and ride quality IMO in most tires today (outside of the really low profile jobs, where you need 38-40psi or better, like my wife's new Pontiac G8)

Also, don't forget that there is also a sensor in your spare tire - so make sure it is up to the proper pressure too.

Thanks for the info. And, that isn't cold for me... I love it (I'm looking forward to winter!). It's just nice becaue it is always a good 10-15 degrees "colder" at my house than down in Denver Metro (I live in the mountains west of Denver). I was going to check the pressure today. FWIW, the warning light was on again this morning with a 51 degree air temp outside...