Tyre Pressure Sensors

[MaxPrimal]

I need to get a tyre changed and it has a defective pressure sensor in it (the valve is leaking, which I know as I pumped it up in the rain and saw the air bubbling out of it).

Can any old monkey fit a pressure sensor into the wheel if I got one - I am talking about my local KwikFit here in terms of monkeys (no offense if meant if anyone here works for them).

Just wondering as I know the sensor is fitted to the alloy and needs to be done when the tyre is changed ideally. Also one of my rear tyres has a flexible rubber valve so I know it is also missing a sensor so would like that done as well.

Something also tells me I will need it on a lexia to code them to the car is that correct?

Thanks
Max

[DickieG]

Having had the new sensor fitted to the wheel you need a Lexia and a tyre pressure sensor exciter tool then to go through a short procedure to get the car to recognise the new sensor.

[MaxPrimal]

Thanks. My local mechanic has a lexia as I found out this week, so getting it recognised is no issue.

Can places like KwikFit or most other tyre places fit them when they change a tyre or does that need specialist tools / skills beyond what they have?

Maxl

[waynedance]

My sensor leaked and I removed it and cleaned it. It that the only fault leaking?

[miked]

I was told, but have not tried it myself that the valve core is a standard schrader design. You can take one out of a non-sensor valve and put it in yours.
You can get, or kwik-fit should already have a valve tool to extract/insert the valve core and clean the threads.

[MaxPrimal]

My sensor leaked and I removed it and cleaned it. It that the only fault leaking?

AS I said at the top, on one of the tyres there is no sensor at all and I would like one fitted so it would be a case of having the wheel off, the tyre removed and the sensor fitted. The other other one with the leaking valve - it is leaking on the outside of the valve where it joins and seals against the wheel itself, so I am guessing it would need removing for at least a new seal if not sensor.

Oh as another thought my car reports two sensors are missing. One is (rear passenger), no question. Does the car only scan 4 tyres or does it expect one on the spare as well? Just wondering because if it says 2 are missing and it doesn't count the spare there is a reasonable chance the leaking tyre's sensor is duff.

Max

[DickieG]

My local mechanic has a lexia as I found out this week, so getting it recognised is no issue.

Can places like KwikFit or most other tyre places fit them when they change a tyre or does that need specialist tools / skills beyond what they have?

In addition to Lexia you must use the exciter in order to stir the pressure sensor into life, without this tool being used and the tyre inflated to 3.7 bar the car won't recognise the new sensor.

Oh as another thought my car reports two sensors are missing. One is (rear passenger), no question. Does the car only scan 4 tyres or does it expect one on the spare as well?

The system only scans the sensors when they are in motion so a sensor in the spare wheel isn't required.

[Mandrake]

The system only scans the sensors when they are in motion so a sensor in the spare wheel isn't required.

So it only warns you of a flat tyre after you've driven off down the road and destroyed the tyre ? (yes, some people are that unobservant that they wouldn't notice a flat tyre until its too late)

[Lighty]

The new type tyre sensors look like standard tyre valves when fitted, as they are a pull through rubber design, these fit C4 etc.
The Lexia program on my laptop, makes me program all 4 valves when one is changed, however on planet I can just do one.
The new handheld garage devices that most places will be getting soon, can just do one valve, either by excitation with the tool, or by putting in the long reference number.
Also when I purchased a C5 valve this week, it was about half the cost that they were even a few months back

[lexi]

So what if the sensor is ok and working and you are just renewing a tyre?........Is is just a normal tyre change with no re -program?

[Hell Razor5543]

I remember when I got my company Skoda, I was able to have it with tyre pressure monitoring. They way they do it is very simple. There was just a little bit of additional code and a button (used when you had topped up the tyres). The way it worked was very simple. It just added a different level of monitoring to the ABS system. Tyres with the correct pressure levels will rotate known amounts at given speeds. However, one with low pressure will have a different (smaller) circumference, and will spin faster at any given speed. The additional code picks this up, and after a given period of time it would give warning.

[DickieG]

The system only scans the sensors when they are in motion so a sensor in the spare wheel isn't required.

So it only warns you of a flat tyre after you've driven off down the road and destroyed the tyre ?

There's a very good reason for this in that there is a battery within the sensor which wouldn't last very long if it was constantly transmitting

So what if the sensor is ok and working and you are just renewing a tyre?........Is is just a normal tyre change with no re -program?

No, simply fit the new tyre and away you go but make sure the fitter knows that sensors are fitted so that he doesn't use the bead breaker near the sensor.

I remember when I got my company Skoda, I was able to have it with tyre pressure monitoring. They way they do it is very simple. There was just a little bit of additional code and a button (used when you had topped up the tyres). The way it worked was very simple. It just added a different level of monitoring to the ABS system. Tyres with the correct pressure levels will rotate known amounts at given speeds. However, one with low pressure will have a different (smaller) circumference, and will spin faster at any given speed. The additional code picks this up, and after a given period of time it would give warning.

Great idea in theory but in practice these systems give a hell of a lot of false readings especially when travelling at speed to the extent that in my experience they suffer from "Cry Wolf" syndrome which makes it pretty pointless if you can't trust it.

The Lexia program on my laptop, makes me program all 4 valves when one is changed, however on planet I can just do one.

I can program just one on my C5 with Lexia.

Also when I purchased a C5 valve this week, it was about half the cost that they were even a few months back

Don't buy them from a dealer or ex-dealer stock as they don't come with the valve collar/nut, buy a manufacturer one direct from VDO as it's not only cheaper but comes complete with the said collar which should really be changed as they are made from aluminium and can apparently split in time, Neat Autos sell the VDO ones

[Hell Razor5543]

Never had a problem with the Skoda system PROVIDED that when you topped up the air you then reset the system. If you didn't then you could get false alerts. The only time I got an alert I found I had a slow puncture OSR.

[Lighty]

The super cheap one I bought this week was a Schrader one, it had the official Citroen & Peugeot logo on it, and came with the nut