[Tchapin]

Curious at what point the tire sensor alert driver of low pressure? Left mine running today and out of curiousity dropped both front to 5 psi, and no alert.
I refilled them to 35 psi all corners and reset the monitor, but a little curious if anyone has actually got a low pressure warning or if it will go of when it sits on the rim(s)?

 

[93cruiser]

on my 05 tundra, when it got below 25 psi, the light would turn on. i would think the 07 has a similiar setup, but havent read my manual.
sounds like your system is not working correctly.

 

[Torch]

We purchased a new Corvette in 1999. The Vette has the sensors. They work as designed in the Vette. Those will give us an alarm once the tire pressure drops below a certain pressure. If memory serves me right it is 25 or 26 lbs of pressure. Don't know what the Tundra's would be set at.

 

[Skyhammerz]

I have had mine go off a couple of times, the result of slow leaks in the Ragged Trails. The sensor went off at about 28lbs.
I also had a sensor replaced on Thursday, the sensor light would blink for a minute or so then stay on.

 

[tkious]

Just looked at my manual, and all it says is that it illuminates if the pressure is "low". No mention of the psi. The dealer may be able to adjust the value with their computer (don't know).

My wife's Honda has a readout that shows actual psi right on the multifunction display. You can watch it go up as you put air in the tires. Kinda cool.

 

[mln]

I don't know why they need the tire pressue sensors? This truck has 4 wheel anti-lock brakes, they could just use input from the wheel speed detectors. Use a comparator circuit of the 4 wheel speeds and then give you a light if 1 tire is turning at a diffent rate than the others.

 

[hit_em]

if they did it that way then the sensors would be on all the time. because as soon as there was a difference in 1 psi betweend tires the tires would rotate different. therefore making the light come on.

 

[stubblejumper]

if they did it that way then the sensors would be on all the time. because as soon as there was a difference in 1 psi betweend tires the tires would rotate different. therefore making the light come on. __________________

Of course you would have to set the alarm to only trigger if the difference in rpms of the tires was beyond a normal amount with proper tire pressure.

 

[mln]

You would build in a small fudge factor to the program of course. But, it would be smart not to let them get more than a couple PSI low for max tire life anyway. Maybe more people would check their tire pressures then.

For some reason I have this thing about looking at people's tires. I spot several people per month that have low tires. I always let them know and most act thankful, some look at you like you are wasting their time. I try help everyone, but you can't help those that won't help themselves.

 

[dillinja666]

I don't know why they need the tire pressue sensors? This truck has 4 wheel anti-lock brakes, they could just use input from the wheel speed detectors. Use a comparator circuit of the 4 wheel speeds and then give you a light if 1 tire is turning at a diffent rate than the others.

nope, how would the car able to tell a flat tire, or the tire slipping due to traction loss? it cant it would just start correcting for the rotation differance and start setting off your abs and traction control

 

[mln]

The TC/VSC/RSCA systems already have a yaw/pitch sensor I bet. Intigrate them into the system. Possibly make it a minimum of revolutions per wheel before indicating a potential problem. I'm no programming genius but I bet it could be done.

 

[stubblejumper]

Some vehicles do use the abs system to monitor for low tire pressure.

 

[mln]

There you have it. Another idea I thought I could patent but can't. Once again I'm a day late and dollar short.

 

[dillinja666]

Some vehicles do use the abs system to monitor for low tire pressure.

really? which?

 

[stubblejumper]

Some of the GM vehicles such as the Impala my father drives do not appear to use tire pressure sensors on the wheel and tire assemblies,yet they do have low tire pressure alarms.

 

[dillinja666]

Some of the GM vehicles such as the Impala my father drives do not appear to use tire pressure sensors on the wheel and tire assemblies,yet they do have low tire pressure alarms.

most likely they do, they are just useing an totally internal sensor as apposed to a valve stem type. if you want to check, go and look at the valve stem, if its metal ( not cheap chrome plateing on a rubber stem ) then its a sensor. to kill this arguement, there is no way for the computer to tell the differance between a low tire, a tire thats smaller then the rest ( wrong size ) and a slipping tire due to braking and acceleration. the only thing the car can tell is that the stator ring is spinning faster or slower then the rest, and compensates for it by applying brakes or slipping the transmission.

 

[mln]

I think an all electronic system could learn your tire size. Push a button, drive straight ahead and it recognizes the revolutions per wheel. Have to put on the small doughnut spare? No problem, push a buton to temporarily deactivate the system (your doughnut doesn't have a TPMS anyway). Wheel spin due to traction, who cares trac control takes care of that. But you want to say it can't work so the computer senses the acceleration rate of the tire compared to at least two other tires and determines it is not a low tire. Slipping tire due to braking, wrong problem, anti-lock brakes will take over. It would have to be sending zero frequency for a tire to be locked up. A low tire would still be spinning and therefor sending a signal.

 

[mln]

[no_ads]
I see Toyota has built in some service work and parts sales for the future.That was nice of them, NOT!

From the TS Support provided PDF

If the lithium battery is depleted, replace the tire pressure warning valve and transmitter.

[/no_ads]

 

[HOGWILD]

Guess that clears up the spare tire causing light to illuminate!! Man why would you have to buy complete assy instead of a 4$ battery? I could see this causing a lotta sysytems to be dissabled once they have issues due to $$$ to keep system running!!:td: great sysytem for the parts department!!:td: SO whats the projected battery life of this Litium Battery? or should i say 5 lithium batteries!!

 

[mln]

Not only the $100 part is needed but you will have to pay for them to remove/re-install/balance the tire.

I went without this system on every other vehicle I've owned, when it's dead it's it's dead.