My Touareg isn't so sensitive - the monitor specifies 2.3 bar (33 psi) but doesn't trigger at 2.2, only if it drops to 2.1 - mind you the sensors are over 10 years old compared to a nominal battery life of 5 years.
- Nov 16, 2015
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I. Think my 2014 Santa Fe , is the same, Normal tyre pressures are 33, and TMPS warns ast 30 psi. A sensible drop.
- Sep 4, 2011
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The Kuga gives the pressure readings of all 4 tyres so you can see which one is low if warning comes on. So I pump all tyres to the pressures required back and front and then in the menu press set to store them. So if I need the rears a bit higher I put extra pressure in them and then in the menu do a set again to remember them. If one gets low the display shows which tyre it is. Previous motors have needed checking every tyre with a gauge to find which one was causing the warning.
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- Jul 18, 2017
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On the Lexus and also Landcruiser up to 2021, you cannot see the individual pressures. All you get is a warning that one of the tyres is low pressure. I believe this recently changed as the 2025 Yaris shows individual pressures. On all my Jeeps from the 2005 model until the 2018 model individuals pressures were shown.
The sensitivity resulted in you correcting an underinflate tyre, that would be it doing its job to me and that I would be pleased with.
- Jun 20, 2005
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I guess it all depends who when and where the original calibration was done?
I’ll get some photos in the next poor weather
I suspect mine is due to their age as they're slower to change as the tyres warm up than they used to be.
- Jun 20, 2005
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Fred Drift
, are you on the oem battery? I am and have a gut feeling this winter may be its last🙀
I use Tyre Pal sensors, I set the last winter, they went up in the summer, they have been fine, couldn’t be bothered with adjusting daily/weekly/monthly, I just adjusted upper and lower limits, they were still within the tyre specs for the vehicle they are fitted on
No - I changed the main battery at 8 years old - but when I tested it it still had about 60% capacity - unlike all my previous "old" car batteries I couldn't use this in the caravan as it was too big to fit the battery box so gave it my son for his camping trips.
- Jun 20, 2005
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Yes, with tyre warming in use, along with probably the ambient warming, I was thinking along the same lines, pressures will have changed.
Does the UP use derived or directly read pressures, I suspect the former?
If so had the system been set recently to accommodate the tyre wear differences?
Both aspects that have an impact here on true pressures, to derived.
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- Nov 11, 2009
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Your quoted tyre pressures are the cold pressures and so by the time you got to the tyre dealer the tyres would have been warm and did not represent the cold air pressure. So did the tyre have puncture?
- Jan 3, 2012
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The tyre dealer is only around the corner from us so i don"t think it would have got warm also they gave it check front and rears tyres to make sure it was not a puncture and after they pump the rear tyre the light had gone off ,
- Mar 14, 2005
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Just incase you don't know there are two common types of TPM system. The first and most obvious one is where a pressure sensor usually fitted in the cap that goes on the stem transmits either its sensed pressure, or if the pressure falls below a target value set by the cap.
The other system which I seem to have on my VW passat is derived from the antilock braking sensor, and it works on the principle that when travelling in a straight line, both wheels on the same axle should rotate at the same speed. If there is a difference it means one of the wheels radius has changed, and this likely due to a change in pressure. with this system it does not measure the pressure so as long as both wheels on the axle have the same pressure within a reasonable margin it should be happy. So far (4 years in) no problems.
The other system which I seem to have on my VW passat is derived from the antilock braking sensor, and it works on the principle that when travelling in a straight line, both wheels on the same axle should rotate at the same speed. If there is a difference it means one of the wheels radius has changed, and this likely due to a change in pressure. with this system it does not measure the pressure so as long as both wheels on the axle have the same pressure within a reasonable margin it should be happy. So far (4 years in) no problems.
The type fitted in the cap of the valve stem are usually just aftermarket units, like Tyrepal, not usually originally fitted to new cars.
Most cars that don't use the ABS system use a sensor attached to the tyre valve but inside the tyre - the valve stems are rigid alloy, not flexible rubber - a nominal 5-year battery is integral with the sensor and the whole valve/sensor/battery needs to be replaced when the battery fails.
I don't think this is quite complete, in that I thought the VW system does accommodate different rotational speeds between wheels for correcting for tyre wear? So they don't have to rotate at the same speed, just rotate at expected similar speeds, clearly also on running for long enough to average out cornering effects.
Our Mk 7 Golf's I have had to shall we say "synchronise" for wear by accepting a warning that I had confidently confirmed to myself was only due to wear, this was directly after I change my wearing fronts to the rear.
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