[Berty]

I have just been reading the manual about tyre pressure monitoring and it mentions there is a sensor In each of the valves. My question is when you need a new tyre do you need to get a new valve sensor or do you use the same one. In the past When I get new tyres they always change the valve for a new one.

 

[TheScotsman]

I too have experience of valves being replaced when having new tyres fitted, but I have never had tyre pressure monitoring on a car before. I can imagine this could end up being an expensive tyre replacement if this was the case.

 

[johnan]

The sensor batteries will last for about 5 years plus or minus, so I have read, and that us the only reason they should need replaced apart from a fault developing in one.

Mini tyres will probably last a couple of years if driven enthusiastically so I reckon it may be necessary to replace the sensors at the second or third tyre change or pre MOT if one has stopped working, as they have to work for an MOT pass. Or at least the dash warning light has to work properly which obviously means so should the sensors.

To replace the sensors at up to £200, would be a bit much to add to the cost of a set of new tyres whenever you needed to change the tyres!

 

[TheScotsman]

That £200 is that per sensor or is that a set of four?

 

[texy]

Ether way, the OP's question still stands - are they a 'special' valve, part of the wheel, or a seperate part? I read they they are £200 per set of 4 - they aren't going to be £200 each, ie more than a tyre are they.
Texy

 

[texy]

FYI I had a puncture on the 2nd day of ownership and needed a tyre replacement. Because of my uncertainty over this issue I just went back to me dealer, way I paid over the top tyre cost.
By the time I need another tyre I hope the question is answered.
Texy

 

[jeremybingham]

sensors

Hi there from what I understand the sensor should be ok for around 5 years or more re battery;when that is flat it is at mo about £70 per wheel to replace-gulp!When you need a new tyre I assume they will use the old sensor, but there are valve service kits available on ebay for little money ie just a bit more than a standard valve, if you look around. By the way, our American friends seem to be able to source the sensors for lots less than we can here-nearer £100 for a set! Grrr

 

[jeremybingham]

Just looked on ebay, for BM's and Country mans which I assume will use the same, a valve service kit is a tenner!

 

[johnan]

Each sensor is a separate sealed unit consisting of the battery, pressure sensor and radio transmitter, encapsulated together and not possible to dismantle to repair or replace batteries.


Each one in the UK is supposed to be between £50 and £70 I believe but I would expect the price to come down as they are now mandatory on new UK cars and should become common replacement items.

 

[texy]

OK, but where exactly is it fitted? Where the valve goes, but between the tyre and the valve?
Can it be changed at home (as long as you can re inflate your tyres).
T.

 

[johnan]

The TPMS sensor unit is just like a tyre valve but at the bottom, the bit inside the tyre, is the encapsulated battery, pressure sensor and radio.
They are fitted by removing the tyre, fitting the sensor through the valve hole from the inside and then refitting the tyre. Then inflating the tyre.

So unless you have tyre removal equipment, it is not really a home job.

There seems to be development work going on all the time on these things, along the lines of battery-less, or at least self recharging sensors, and universal sensors which will probably be cheaper than bespoke BMW ones.
Bit of a pain really, thanks to the EU for making them compulsory over here!

 

[Angib]

The pressure sensor and the valve stem are all part of the same item. The stem is metal so so that removes one reason to replace valve stems when changing tyres (the deterioration of the rubber valve stem). However the Real OEM diagram of the pressure sensor shows that a new stem (item 3) can be fitted to the pressure sensor if required (it shows a US price of $14, so about £10). It does list different colour stems (Orange, Schwarz, Gr[FONT=&quot]ü[/FONT]n, Gelb), so expect that as the next wheel accessory for the true fashion victim.....

I think replacing valve stems at tyre changes is some sort of throwback to when tyres weren't tubeless, and replacing the inner tube at the same time as fitting a new tyre was common practice. I'm not convinced it is valuable nowadays.

 

[Matt]

all sounds a bit odd to me.... have any of you actually had to calibrate the tpms like me?

if it was a sensor fitted in the valve, one wouldnt expect to have to dive for a few miles while the system normalises and calibrates, after pumping up the tire to correct pressure (which is extremely high considering my previous minis at ~34psi... now its over 40psi).

some systems use the abs sensor to detect slight variations in wheel rolling circumference... and thats what i thought was fitted to the latest mini's - due to this stupid calibration process.

my kuga has tpms and it knows the tire pressure as soon as i start the car up... which would point to the type of sensors you guys are talking about, but on the ford.

does anyone actually know for sure what kind of system is used on the mini?

 

[Solar red]

These are on EBay.

 

[jeremybingham]

Hi all, you can buy replacement valves for the tpms when you change tyre- about a tenner, but the whole lot when the battery goes is £70 ish! I have winter tyres so am going to have to have another set of tpms's -grrr, very expensive,but apparently dexel tyres do a universal fit tpms at £50 so that would be cheaper than shipping a set from the usa! Any one any experience of this?

 

[mishima]

all sounds a bit odd to me.... have any of you actually had to calibrate the tpms like me?

if it was a sensor fitted in the valve, one wouldnt expect to have to dive for a few miles while the system normalises and calibrates

The owner's manual says it takes about 30km to reset the system. So i suppose the sensor is fitted in the valve.

 

[catflap]

Tyre Pressure and Temperature Measurement

My wife's new MCS has the 'full' monitoring system just like that on my BMW X5. It measures the actual pressure and temperature in each tyre. By default here in the UK the tyre temperature is not displayed though i've coded both my X5 and the MCS to show the temperature alongside the pressure reading on the iDrive display.

 

[jeremybingham]

Yes yes and yes all. There is a battery powered transmitter in each tyre. 5 year expected life. The valve is replaceable separately.So yes when you get New tyre you can replace just the valve The reAson we have this stupid system is down to the wonderful eec who have stipulated these must be on any vehicle. Yes the old r56 system used abs to measure diff in wheel speeds but this wasn't deemed accurate enough for run flats so in the name of safety we consumers fork out again. And the movement of the wheel switches the system on! Clever but unnecessarily complex.thanks a lot.Eec my vote is for out!

 

[Paul Hemsley]

Blimey !
Some people say that a car simply gets you from A to B
Surely this is no longer the case.
Yes I want much more than that but …..
Is there some form of University degree in Motoring Technology available ?
Yes I am getting older but still no wiser to "The Modern Way"
Is it all a con ?

 

[droffilc]

The tyre pressure sensor is attached to the valve inside the wheel. It measures the tyre pressure and if it falls below a certain threshold a warning is displayed on the dash. On most cars inflating the tyre to the correct pressure usually cancels the warning after a few revolutions of the wheel.
A tyre can usually be changed without disturbing the TPS. It is also possible to change the TPS
without dismounting the tyre completely. As mentioned, the sealed battery lasts about five years.
The earlier MINIs had a different system. A warning was shown if wheels on opposite sides of the car rotated at significantly different speeds, caused by the smaller circumference of the tyre with low or no pressure. There was nothing extra installed in the wheel
This system caused many false alarms, especially during spirited driving on loose surfaces and even some roundabouts. I speak from personal experience.
On some cars it is possible to deactivate the TPM system, either officially or unofficially.
I don't know f this is possible with a MINI. It probably depends on which country you're in.
I think it should be allowed everywhere, especially with run flat tyres.
OEM sensors, especially for premium brand cars, tend to be quite expensive but there are now aftermarket alternatives which cost less.
When cars with a TPM system eventually fall into the "banger" category, I expect the drivers will learn to ignore (or tape over) the warning lights caused by dead TPSs.
Hopefully it won't be cause for an MoT failure.