Scotty
I have a 2014 Toyota Tacoma with 67k miles. It's a 4 liter automatic.
No doubt I have a bad tire pressure sensor. Oddly at highway speeds it comes on after driving 22 - 35 miles and stays on. It goes off and stays off until I'm back on at interstate speeds. It doesn't come on at all in Cold NYS weather. It doesn't come on during city driving.
Your thoughts please
Go Bills. Former WNY resident.
Had a similar problem.
Wireless TPMS sensors sit inside the tire and have tiny contacts in them which switch them between two modi - the power-saving parking mode,when they generate one tire pressure-and-temperature signal like every several minutes, and the driving mode with much more frequent signalling. The switching between the two modi is done by centrifugal force and usually happens at 20 kmh (is tire size dependent).
When a sensor starts to go bad, e.g. due to humidity corroding their centrifugal-force-sensing contact, the switching may start happening at different speeds, and / or one of the modi may start working unreliably or stop functioning at all due to this contact, when switching over, not sending electricity through the respective part of the sensor circuitry any more. Normally, once this started, this cannot be fixed. You may want to tolerate that till the sensor dies completely, or replace the sensor immediately. Mine was like 25 USD + tire rebalancing, original ones are indeed more expensive. A normal sensor life is between 4 and 7 years, limited by the sensor battery capacity / lifetime. If you like doing things yourself and are smart, you can replace such a sensor with your own hands, without the need to rebalance the tire afterwards: it is not a complicated job. Some even replace those batteries instead of replacing sensors as a whole, but it is not an easy job to do, since batteries are often sealed using a compound which also covers the sensor electronic board, and when you try removing the compound, probability is high that you will also damage the board with its tiny components.
TPMS are just another electronic nightmare that manufacturers seem to think we all need but don't. I have a tire gauge and I know how to use it.
The good thing about having sensors, as opposed of just relying on the manual tire gauge, is - and Ive been there - that with sensors, when your tire gets punctured at high speeds, probability is much higher that you will have enough time to safely come to a stop, before your flattening tire gets "chewed up", your expensive rim destroyed, and your car probably coming into an uncontrolled spin. Sensors notice and clearly indicate rapid pressure loss significantly earlier than a driver does sense this loss and understands the reason of the changed vehicle behavior.
Good point but I still have no use for them. I know what a flat tire feels like.
Not trying to argue, just trying to clarify my point, which is for me not always easy with my learnt English. Almost every driver knows what flat tires feel like, unfortunately. That is not what I was trying to say.
A human has no ways of sensing tire pressure loss directly. He can only sense subsequent tire geometry changes, and significant ones. When a tire gets low-pressure-related deformations, severe enough for the driver to sense them via tangible vehicle behavior changes, some negative consequences - especially at high speeds - may already have become unavoidable. Those ranging, depending on the specific situation, from chewed-up tires to the vehicle pieces hanging on the close-by trees. The TPMS senses tire pressure losses directly and immediately - even before they had a chance to cause any tangible tire geometry changes - which under certain circumstances gives the driver invaluable additional seconds (and - at high speeds- hundreds of feet of relatively safe driving range) for properly reacting and avoiding the most undesired consequences. Of course TPMS is not guaranteed to save you, but imo the better surviveability chances this system may provide to me under certain circumstances are (for me personally) way worth the price of one, or even four, tiny sensors which are neither hard to get nor to install.
Please do not misinterpret this lengthy explanation as an attempt to lecture you or show any disrespect towards your opinion..
Opinions are like armpits, everybody's got 'em. I still will never have any use for TPMS.
Have to agree with dontknowler here. By the time you feel a flat tire it could be too late. The gauge in your glove compartment won’t do you any good when you run over something on the highway.
Mine hasn’t been a nightmare
What you are saying is the TPMS warning light is coming on at highway speeds (after some time) then turns off at lower (non highway) speeds. On your instrument gauge cluster, what are the tire pressures when this happens? Also, out of curiosity do you have a full-system scan tool that can look to see/record the TPMS tire pressure values as seen by the Body Control Module (BCM)? A regular OBDII scanner won’t be able to tell you that information, and I prefer to see what data the computer itself is seeing (versus what is displayed on your gauge cluster for TPMS). Any anomalies in that recording when the light comes on? That’s where I would start to better understand what is going on.
