Remote motor tyre pressure measurement

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Many times, when I am driving my car, I worry about the tyre pressures. Why can't I have a gauge or friendly light to tell me they're ok? In my head, I have designed many different systems for the measurement and the telemetry. I realize it isn't 'very easy' but there's no reason it can't be done. Why isn't it marketed to people as another 'peace of mind' gizmo? It's far less smart than automatic parallel parking!
 
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I have them on my Chrysler. They broadcast to my heads-up display and tell me when the pressure in each tire is low or high.
 
It is commonly called TPMS, for Tire Pressure Monitoring System.

tpms_typical.jpg
 
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sophiecentaur said:
Why can't I have a gauge or friendly light to tell me they're ok?
Most new cars do have this. My 2012 civic tells me when my tire pressure is low.
 
Wait wait wait. Wait.

It's SophieCentaur. I knew something was wrong here.

We only have Tire Pressure Monitoring Systems.

Sophie, if you're looking for Tyre Pressure Monitoring Systems, I'm afraid you're out of luck.
 
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Does anyone know how the sensing is done and what the telemetry system is? I found some fairly generic stuff on Wiki etc. but what about the details?
I like the indirect method of comparing wheel speeds.
 
two types of monitoring systems
direct reading – small transmitter is attached to tire valve stem and directly reads pressure of the tire. if psi changes it will alert the dash board light. has to have unique code so other vehicle s with this type monitoring system will not false trigger your dash light. cost is about $100 each form manufacturer though after market replacement transmitters are half the price. these are subject to damage if you buy a new set of tires and the local tire gorilla operating the mechanical mount/dismount tire changer is not careful.
Indirect reading systems – use the ABS (anti lock brake ) sensor on each wheel. If one tire has lower PSI reading it will have smaller radius and different RPM count versus the other 3 tires and will alert the dash light. pretty bullet proof can simple software to monitor.

with todays quality control and advanced tire manufacturing techniques you are pretty safe regarding tire failures.
Things you can do if you really want to reduce the odds of tire failure. Inspect them for cuts, wear, periodically. Check tire air pressure monthly. Use nitrogen to inflate. Nitrogen is a fatter molecule and will not bleed through the side wall like compressed air. Nitrogen has less moisture content than compressed air and will not grow as much as compressed air due to heat.

Tire failure is the least of your worries today driving. The real danger is the texting teenager. I was following a young driver who was texting and had to slam on my brakes. almost got in an accident. made me spill my beer!
 
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I don't understand how people can't feel that their tyre pressures are off.

Also why would you want a light to tell you everything is ok. Every manufacturer is moving away from 'gauges' to idiot lights that let you know when something is going wrong. No lights, no problem.
 
xxChrisxx said:
I don't understand how people can't feel that their tyre pressures are off.

Also why would you want a light to tell you everything is ok. Every manufacturer is moving away from 'gauges' to idiot lights that let you know when something is going wrong. No lights, no problem.

You can tell if you had 3 tires at 36psi and one at 32? I doubt that very much, at least in normal, everyday driving.
 
On a car I'm familiar with yes I can. Though as part of my job I have done a lot of NVH and ride and handling work.

It's not a superhuman skill, I'm pretty sure that most people can physically feel the difference, they just don't register it as an issue. Or even if they do they aren't sure what's causing it.