Why did my TPMS light turn on?

[RRey0456]

Hello,

My TMPS light turned on the other day. The weird thing is I don't have TPMS on the my wheels. I have the wheels with hubcaps, my tire pressure is correct and it turned on while it was raining but later that day it turned back off and hasn't returned.

Any ideas?

[lovemysantafe]

If your vehicle was produced after September 1, 2007 then it has TPMS and I guarantee you if you have that light and it came on, then you have the system. Alloys or hubcaps don't make any sort of difference as the sensor is in the valve stem inside the wheel.

It's possible that one of your tires was right on the cusp of activation and driving the car warmed the air in the tires, causing it to expand and turning off the light. It's also possible that your TPMS sensor picked up a stray radio wave that tricked it into thinking a tire was low. This has happened before so it's not unheard of.

[RRey0456]

Radio waves? Would you know were I can find detailed info on Tire pressure monitoring systems and how they work?
I'll check google or YouTube

I wasn't aware that the sensors are in the valve stems either. Thank you.
Would it be possible to put my current TPMS on new wheels and tires?
I have a 2008 GLS and it's only a light on the dash no specific info regarding psi. Do I have a range of numbers that it allows me to stay in-between?

[pare_john]

TPMS does not always work with the sensors in the wheels. A lot of time tire pressure is monitored through the wheel speed sensors. As a tire gets very low on air the wheel speed sensor can detect this because that wheel now turns at a different rate.

[peacefrog_0521]

That's odd. My TPMS light just turned on last week, about the same time. I checked all of my tires and they are not low, they are all in the 30's as usual. Wondering if the Midwest got hit by radio waves that knocked out everyone's TPMS. Maybe need to call Leonard Nimoy to go "In Search Of."

[nb_mike]

I have had the same problem numerous times with my 2009 Genesis sedan. I was in Chicago recently and the two front tires showed they were low. this seems to happen whenever the temperature drops because that will cause air pressure to drop. It tends to happen in Fall the first time it gets cooler. The only solution is to put a bit more air in. I have a portable air pump that works off of auto cigarette lighter to turn it off. It is a real pain at times.
It never is just one tire. I've even had all four showing low pressure. This is just another government program to improve gas mileage. Total BS!

[RRey0456]

Originally Posted by peacefrog_0521

Wondering if the Midwest got hit by radio waves that knocked out everyone's TPMS. Maybe need to call Leonard Nimoy to go "In Search Of."

Right, that's funny.
Idk I guess I'll just fill up abit over 30 since it's most likely only going to get cooler from here.

[rmissourimule]

I owned two Sonatas of this vintage and almost certainly the cause is lowered air pressure in the tires. Usually airing them up to about 35 psi will make them go off within a couple of miles or less.

I can't prove this but mine was delivered with Nitrogen in the tires which is supposed to eliminate this problem as it is said not to be affected by the outside temperature.

This is most often seen by all vehicles in the winter months when the temperatures drop significantly. It is probably not serious but just a lower air pressure than it should have.

If after you air it up and it still does not go off you should have it serviced.

The TPMS valves should work in aftermarket wheels. I've have used them in alloys I purchased to replace he stock steel wheels. No problem. Just don't tighten them down too tight or you can break the aluminum valve stems. And these little buggers can get expensive and will need to be reprogrammed if replaced.

[RRey0456]

Originally Posted by rmissourimule

I owned two Sonatas of this vintage and almost certainly the cause is lowered air pressure in the tires. Usually airing them up to about 35 psi will make them go off within a couple of miles or less.

I can't prove this but mine was delivered with Nitrogen in the tires which is supposed to eliminate this problem as it is said not to be affected by the outside temperature.

This is most often seen by all vehicles in the winter months when the temperatures drop significantly. It is probably not serious but just a lower air pressure than it should have.

If after you air it up and it still does not go off you should have it serviced.

The TPMS valves should work in aftermarket wheels. I've have used them in alloys I purchased to replace he stock steel wheels. No problem. Just don't tighten them down too tight or you can break the aluminum valve stems. And these little buggers can get expensive and will need to be reprogrammed if replaced.

Thanks for the info.
I've been looking for used stock alloys for some time now and was wondering wether the TPMS I currently have on the steel ones would be transferable.

So when I get ahold of some new/used rims to replace my current ones do I simply screw the current valve stems off? Gently of course keeping in mind what you said about them being fragile.

[lovemysantafe]

Yep. The valve stems can be swapped to your new rims but it's a job best left to a professional. When you have them switched over, make sure they know it's a TPMS stem so they can break the tire off properly otherwise they risk shearing off the business end of the sensor when breaking the bead.