I was up in Northern NH today. About 12 degrees out. I was up in the Mountains. Coming down the road out of the mountains, the TPMS did it's little "DING" thing and the light came on. Message came on saying low tire pressure. I thought I hit a nail or something, so started looking for an exit off the highway to check. But I was in a place called Frankonia Notch which was pretty snowy and not many places to pull over safely. So anyway about a minute or two after it came on it went off and the message cleared itself. Do you think the altitude change had anything to do with it? Just wondering if anyone in places like the Rockies has to deal with that? Just got me wondering.
BTW I still have not had any problems with snow packing in around the gear selector linkage yet. And we have had plenty of snow up here. Pretty much powder though. And I did manage to get the MPG up to 26 MPG coming down the Mountains today too! LOL.

 

I think you hit the nail on the head... changes in altitude obviously affect compressed air pressures.

 

For sure, my brother inlaw got rid of his sensors and somehow disabled the system on his Ford F150 because of that.

 

My light randomly comes on. I check all the pressures and they're normal. Then after a few days it goes away. Its happened to me twice now.

 

Also, not to state the obvious here, temperature will effect the pressure. Sometimes you might start your truck in the mornings and it will ding at you saying low pressure, but once you start driving and the tires heat up the air, it will expand again and the light will go off. Just another possibility since you said it was 12 degrees.

 

That is why it startled me, because I had already been driving for about a half hour. I used to keep 32 lbs in the tires during the Summer but had to raise it to 35-36 lbs to keep the TPMS from coming on all the time in the colder temps. -12 yesterday morning and the warning light never came on. So I am guessing the altitude difference had something to do with it. You can see the grade I was going down when it came on in this pic. I almost all the way out of the Mountains by then.....