Tyre pressure

[Henry]

OK, this isn't strictly speaking a Volvo question -- but this is the
only auto group I follow.

On these new-fangled cars, the dashboard computer can give you the
pressure in each of the tyres. How do they do that?

cheers,

Henry

 

[TimR]

OK, this isn't strictly speaking a Volvo question -- but this is the
only auto group I follow.

On these new-fangled cars, the dashboard computer can give you the
pressure in each of the tyres. How do they do that?

cheers,

Henry

Sensor on the wheelrim (inside the tyre) and wireless link to receiver.

HTH

Tim

 

[Tony]

Sensor on the wheelrim (inside the tyre) and wireless link to receiver.

Obviously this means they are battery powered and have a limited life
usually 5-7 years, afterwhich they have to be replaced. Not sure if any
have replacable batteries. I would imaging battery life will get longer
for newer devices.

I have had an aftermarket set in for >5 years now still working well,
although I have had a few problems because of the special valves it
needed to mount the sensors. Mounting to the rim provides a much better
solution.

The last point is that they are quite inaccurate (even though they
measure temp aswell), and many manufacturers specifying them as OE have
run into problems caused by accuracy, such as unnecessary warnings to
the driver or refusing to drive anywhere because it thinks the tyre
pressure is too low when it isn't.

 

[Henry]

run into problems ... such as ...
refusing to drive anywhere because it thinks the tyre
pressure is too low when it isn't.

Ha! That's the danger of over-sophistication, isn't it? 'Great new
ideas' have to be made 99% reliable before they're acceptable.

Reminds me of when I was a kid, back in the '60s, and the Corvettes came
out with retractable headlights. 'Man, that's _cool_!' I said. 'Oh,
yeah, it's 'cool', all right', said my dad. 'But it's not new. There
were cars in the old days that had those too', he said. 'They were so
'cool' that in the winter they'd freeze shut and you'd get stuck
somewhere, unable to drive home at night!'

cheers,

Henry