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Was in a garage filling up this afternoon and saw a brand new tyre pump on the forecourt so thought I would check/top up tyre pressures.
All 4 tyres were 4-6 psi below recommended but I had no warning from the car. I know it works as it has previously alerted me to a tyre being low, by 4psi on that occaision but nothing this time on all 4!!!

Any thoughts much appreciated.

Regards

Tim
 

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Was in a garage filling up this afternoon and saw a brand new tyre pump on the forecourt so thought I would check/top up tyre pressures.
All 4 tyres were 4-6 psi below recommended but I had no warning from the car. I know it works as it has previously alerted me to a tyre being low, by 4psi on that occaision but nothing this time on all 4!!!

Any thoughts much appreciated.

Regards

Tim
I think you should stop relying on your tyre pressure guage in your car and use a manual one! ;) :D :p
 

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I think you should stop relying on your tyre pressure guage in your car and use a manual one!
I agree. ;)

If it was the gauge on the pump you checked with, I wouldn't trust them to be at overly accurate. :rolleyes: They're fine for an emergency or rough guide, but IMHO not for normal use. Anyway, it's poor practise to check the tyre pressures after driving as the tyre heating up affects the pressure and varying distances or speeds affect the amount of heating, so the tyre pressures will be inconsistent - tyre pressures are meant to be checked cold, ideally after sitting overnight or at least after 2 hours. Even having the car parked with one side facing the sun can affect the pressures between sides. :)

Automatic monitoring systems are fine as a back up, but I'd guess a fair number of folk come to rely on them at the expense of doing a proper pressure check every week or two. :confused:

Mind you, as I alluded to, there's no guaranteeing the accuracy of the gauge or how it compares with another that you may have used when you set the datum pressure, so they might well have still been within the tolerance of when the datum level was set for the warning - especially as they were all different by approximately the same amount.

As an aside, in my TDI there was a nice little empty slot in the took kit foam that a pencil type tyre pressure gauge fitted in nicely.
 

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I believe that there 2 types of pressure monitoring.
The one we have in Aus measures the actual turning of the wheels by the ABS ESP andother sensors and if 1 tyre is flatter than the others it will turn at a different speed.
I have been told that this difference needs to be abot 4 or 5 PSI
If this difference continues for more than 15 seconds then the alert comes on

If all 4 tyres lose pressure at the same time then the difference is not picked up and no warning given

As per others I would not rely on this as being the way of checking tyre pressures a good quality manual hand held lives in my door pocket.
 

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I believe that there 2 types of pressure monitoring.
The one we have in Aus measures the actual turning of the wheels by the ABS ESP andother sensors and if 1 tyre is flatter than the others it will turn at a different speed.
I have been told that this difference needs to be abot 4 or 5 PSI
If this difference continues for more than 15 seconds then the alert comes on

If all 4 tyres lose pressure at the same time then the difference is not picked up and no warning given

As per others I would not rely on this as being the way of checking tyre pressures a good quality manual hand held lives in my door pocket.

100% correct....

The tyre pressure monitoring is not intended to eliminate conventional pressure testing using a gauge - it serves to indicate a tyre losing pressure so the driver can pull over in a safe place before the flat tyre becomes a safety hazard. It also has the fringe benefit of minimising damage to the tyre/wheel rim by minimising the necessity to drive on a fully flat tyre to a safe location to change it.

We have had one warning from the system on our Eos when one of the front tyres was 20 kPa [3psi] less than the other tyres - this had just started to indicate its presence by the car wanting to pull to one side on a flat road.

There are two different monitoring systems for the Eos depending on the country of delivery. Fred K is correct about Australian compliance cars system using the ABS system for monitoring purposes. We also carry a tyre pressure gauge as I have found service station gauges to be very unreliable due to the way they are treated by users.
 

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I have a 2010 VW Eos and the weather was cold this morning, with frost on the car. Anyway, the tire pressure light came on. I called VW and they said it's due to the cold and the light will go off. If this is the case...will this happen all the time with a change in the weather?
 

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I have a 2010 VW Eos and the weather was cold this morning, with frost on the car. Anyway, the tire pressure light came on. I called VW and they said it's due to the cold and the light will go off. If this is the case...will this happen all the time with a change in the weather?

If you are in the USA with their TPMS system, the tyre pressure will reduce as the temperature drops [remember Boyle's Law from your Physics/Science classes PV/T = constant where P = Pressure, V = Volume and T = Temperature in degrees Kelvin/Absolute] - If you use pressures at the lower end of the specified range, the tyre pressure can go below the minimum and activate the sensor if the temperature is low enough. The tyre pressure will increase as the tyre warms up when you start driving hence your dealer's advice.

Just try increasing your tyre pressure to the top end of the range and this should solve the problem. I think this is the first mention of cold weather pressure monitoring activation on this forum.
 

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