Tpms

[Thespannerman]

Sorry guys, more newby questions

Does, or should the tpms system show the actual tyre pressures. My old discovery did.

I have tried setting the system and it shows green circles against all 4 wheels, but no pressures showing.

If it doesn’t, does the system just use the reference pressure and notify you if it differs by a certain amount.

Cheers
Al

[Moomoo]

Originally Posted by Thespannerman

Sorry guys, more newby questions

Does, or should the tpms system show the actual tyre pressures. My old discovery did.

I have tried setting the system and it shows green circles against all 4 wheels, but no pressures showing.

If it doesn’t, does the system just use the reference pressure and notify you if it differs by a certain amount.

Cheers
Al

I pretty sure it only tells you that attention is required when a pressure drops on a tyre.

[Wizzpop]

Originally Posted by Moomoo

I pretty sure it only tells you that attention is required when a pressure drops on a tyre.

Correct, there is no provision for measuring actual tyre pressure. The system relies on the rotational speed of the wheels using the abs sensors (I think)
Early Volvos had the special (expensive) valves which did measure the pressures. Unforunately the bluetooth or whatever connection from the wheel to the car interfered with other systems.

[Lexman8]

Originally Posted by Wizzpop

The system relies on the rotational speed of the wheels using the abs sensors (I think)

That's correct.

[nu11eaf]

As above, you will get a warning message come up on the driver display if any tyre pressure drops. Or indeed if they go too high, I once had this when driving on a long run on a very hot day, the tyre pressure were a few psi high, I have had two warnings of low pressure, one was a rapid deflation puncture and and the other a slow puncture after picking up a screw in the tyre.

[key76]

It's utter crap quite frankly. Every car I have owned since 2003 has had "proper" TPMS that shows the pressures. But Volvo seem to think it's acceptable to cut corners and save money (for them) by putting an inferior system in.

Even my wife's Ford Fiesta will show the pressures, but not a £50k+ so called premium car.

Very petty I know, but one of the many reasons this will be my first and last Volvo.

[Moomoo]

Originally Posted by key76

It's utter crap quite frankly. Every car I have owned since 2003 has had "proper" TPMS that shows the pressures. But Volvo seem to think it's acceptable to cut corners and save money (for them) by putting an inferior system in.

Even my wife's Ford Fiesta will show the pressures, but not a £50k+ so called premium car.

Very petty I know, but one of the many reasons this will be my first and last Volvo.

I think tyre pressure monitoring is only important with runflat tyres .

Ordinary tyres are a driver responsibility, then again, I’m a dinosaur.

[OldEngineer]

Originally Posted by key76

It's utter crap quite frankly. Every car I have owned since 2003 has had "proper" TPMS that shows the pressures. But Volvo seem to think it's acceptable to cut corners and save money (for them) by putting an inferior system in.

Even my wife's Ford Fiesta will show the pressures, but not a £50k+ so called premium car.

Very petty I know, but one of the many reasons this will be my first and last Volvo.

These systems you like have corroding sensors and are hell to deal with in tyre repairs. The better Volvo rotational system is exactly what the major safety systems use. So ABS can measure as low as 1MPH difference (although TPMS is not set this low). Traction Control and Electronic Stability Control are major safety systems comparing rotational speeds.

The Volvo TPMS allows you to set a control pressure and then monitors changes from this control pressure

[BigBugger]

I thought the same, I picked up my 2019 XC90 a couple of weeks ago, my previous Santa Fe gave actual pressures, and they were accurate too.

[Thespannerman]

Ok cheers. Yes a bit disappointing on a premium car not to have actual pressures shown. Another Volvo quirk fir me to have to get used to

Al