Tire pressure low

Usually marks low tire when either the tires have 29 pounds or less. Prius use 35.lbs front and 33 lbs rear

Posted via the PriusChat mobile app.

 

The warning means at least one tire has dropped 25%* below the value you've set (with the tpms reset procedure, see Owner's Manual). I would check them all with a decent tire gauge as soon as possible, top them up as required. At the very least: look them over.

(* This is the pressure drop factor I've read here a few times, no backup documentation)

That said, I've had one instance when the warning went off for no apparent reason. I raised them all about 4 pounds and the light went out. A few days later I lowered them back to usual, the light stayed off.

I've had one other instance, in that case one tire had got below the threshold, was one with a small finishing nail in the tread IIRC, it was leaking very slowly.

 

One is enough. But it could be multiple tires too, so check them all.

Anywhere from seconds to weeks, depending on how fast or slow the leak is. But since it means a tire is at least 25% low, this is sufficient reason to get check promptly, and re-inflate right away.

And like Mendel, I have had a spurious warning (several times now), where nothing was actually low. Updated ScanGauge firmware now shows that a specific sensor does not get read by the TPMS system for too long a period. This spurious condition has been resolving itself in 5 to 20 minutes, but then repeats several times in the same day. Then doesn't reappear again for months. And it has happened on both summer and winter wheel sets, i.e. different sensors.

 

Any time my light came on my one of my tires was low, usually in the 20's psi range.
Most often in cold weather.

 

Installed a $50 external TPMS device. No more guessing. I know exactly what each tire pressures are real time, all the time, car on or off, moving or parked. Very Happy.

 

Pressure and temperature? Interesting.

 

Yap, both pressure and temp are real time and do not require the car to be on. The monitor ping every so often after awake, maybe about every 2-3min. There is an issue of durability, but if it lasts a few years I will be happy.

 

Get tire assistant app and connect it by Bluetooth

Posted via the PriusChat mobile app.

 

Yes. After the ScanGauge-II firmware upgrade a year ago, my unit came back with X-Gauges for both pressure and temperature. So the other TPMS and OBDII port monitors ought to have temperature also.

 

Where did you get the gauge? Does it attach to the ODB port or read the TPMS sensors over the air?
Thanks.


Posted via the PriusChat mobile app.

 

I got it from Amazon, but you can probably get a similar one from any auto parts store or other on-line merchants. The price ranges from $30-$250, but my feeling is they are all made in China with very cheap components. One I got is this one.

In case you have ad-block, the product name is Favoto TPMS Tire Pressure Monitoring System Solar Power Universal Wireless Car Alarm System with 4 External Sensors Real-time Displays 4 Tires' Pressure & Temperature for Car (22-87 PSI/1.5-6.0 BAR)

It is with external sensors that screw on to each valve stem. Very easy installation, but due to the location of the sensor, they are prone to damage from elements.

 

So did you check tire pressure and they are all OK? Your car is 6 years old, you may have one or more of TPMS sensor inside of the tire with a low but not yet completely dead battery. They suppose to last 7-10 years, but I had mine started going out at 6 years.

 

Maybe. What tire pressures did you measure?

Or did you measure it at all? If not, naughty naughty.

Cold weather does trigger TPMS warnings, but only when the pressures are already getting somewhat low anyway, such as from a slow leak or ordinary seepage. So if you are getting low pressure warnings at all, then at least one of your tires needs to be topped up. Warmer weather alone will not get it back up to where is should be.

 

Of course, you could always buy a tire pressure guage and check the tire pressures(when cold) every 2 or 3 weeks...
Even with the tire pressure monitors you should be checking them.

 

And be sure to ask Santa for a tire pressure gauge. This is something every driver (of their own car, not necessarily those who only rent) should have, so pressure checks can be at their own convenience, not restricted to when at a gas station.

 

Just noticed my daughter's 2010 Honda Civic has two TPMS warning lights, one for low pressure, and second one for bad sensor (eg; dead battery)...so that way the system is still useful even if one or two tires is not reading.