Spare TPMS issues

So I know there's people who've had this issue before but I can't seem to fix my problem....

Now that it's getting cold my TPMS light keeps comin on due to my spare staying cold..I've checked the pressure in all the tires every time it's happened and it's always the spare that's "low". It'll only be off by a few pounds due to it gettin cold and I'm not sure what to do about it.

I'd rather not over-inflate it for compensation just incase I ever need it, don't want it higher than it supposed to be.

Any suggestions other than just ignoring the light like I've been doin?

 

What year is your truck?

 

2006

 

Seems strange that you keep getting the TPMS light popping up even if the spare is getting a little low ? They have batteries in the sensors and you have an 06 correct ?
They say the batteries are only good for 5 years .
My first guess would be you have a dead or dying battery . Dont chance it though
I think its a simple fix but gonna cost ya .
Find somebody that can assist you with the diagnostics of the TPMS system .

 

On my 06, that would happen to me.
I dropped the spare, flipped it over to make getting to the valve easier when the colder weather triggered it.
It only happened a couple of times in 5 yrs.
If it happens a lot, maybe something is up with the sensor battery?
Ooops someone above said the same thing.

 

I've kept all my spares at the max PSI on the sidewall. It's easier to take air out of a tire than to put air in when you're in a pinch.

 

Awesome idea flipping the spare !!!!

 

Batteries are a good thought that I hadn't considered as this is my first vehicle with em..

I've already flipped my spare but thanks for that thought too Simon's Mom..

And Texoma... I've thought about this too but if the TPMS is working right, shouldn't it also detect the overly high pressure? Plus I don't really like this idea because I know I'd forget to drop the pressure if I ever need it.. Ya I know I'm being difficult there but still

 

TPMS only trip on low pressure, and you'll only be riding on the spare temporarily. Plus it's better for the tire to have more pressure than to not have enough. Nothing beats being on the side of the road with a flat spare, once is enough.

 

I live in Canada and let me tell ya , its flippin cold here . I have yet to check the pressure of my spare tire . My truck is a 2010 mind you .
What I am trying to say is that living in a much colder climate , you would think that I would have to check my tires more often . Never had an issue with the TPMS when its very cold outside . I beleive the sensors have a few degrees variance . With that said , maybe you have a slow leak in the spare if it continues to drop in pressure . I still think from your explanation that you need to have the TPMS scanned . Sure sounds like a dying battery

 

Mine kept loosing air in the right front. Ended up I need to tighten the nut that holds the sensor in place.

 

It also triggers on greater than 10psi differential between any two tires, so 40 in the spare and 29 in a roller will trigger it.

Just blow them all up to 35 and call it good.
The dealer probably reset the system at the 29/28 or whatever the door pillar says.
Personally, I run 40+

 

I have o6 sport trd and all of mine except one have dead battery's I had them scanned at Americas tires and the dealer. Only did the dealer because my wife works there and it was free for her to have it checked.

 

I've had the same problem when the temperature drops... the tires heat up causing the pressure to rise but the spare stays ice cold. What you'll need to do in the winter months is keep the spare a few pounds over the others to compensate for it. If you need the spare in an emergecy you'll be fine. The light triggers when there's a 25% difference between the sensors... which comes out to around 8 psi.

 

Thanks for all the responses guys. For now thy seem to be holdin out. I used the el-chepo pump at sheetz the other day and set em all to ~32, or at least that's what that pump said if you trust it... For now the lights off and stayin so, we'll see how long it holds.

 

10psi
Mine was dead nuts on 25psi in the low tire and 35 in the highest when I picked up a nail and it came on.

 

Not to play devils advocate but w all know how computer systems (especially small ones that take a lot of wear) can be different on each truck, it wouldn't surprise me if yours was 10psi and his was.. 8 I believe...

 

Yep... 25% difference or more sets off the light.
http://www.toyotatpms.com/tpms-toyota.html
http://toyotatpms.wordpress.com/2012/03/13/oe-tpms-life-expectancy/