TPMS False Alarm

[a3_phil]

In the last week I've had two TPMS false alarms, both times the tyres actual pressures were all either spot on or within 1psi of the stored figures.

Could this just be the heat causing a bit of expansion, or is this likely to be a more fundamental fault?

Quite annoying as the first time we were on a long drive and ended up having to divert to two different garages (first one had no air pump) to check, all the while with screaming infants in the back...

 

[sbarker]

I had this once on my s1 and I was just accelerating on to the motorway and was going across the lanes. I think it works on the basis of the rotational speed of the wheel ie it knows how long for a single rotation based upon correct pressure, so it could be that heat or any wheel slip when driving accelerating could trigger this. I bought a digital tyre pressure gauge and keep in car now. On my wife s mini the t p m s shows you the pressures shame Audi don't use this better system.

 

[a3_phil]

Definitely no tyre slip on either occasion as I was driving like a granny in traffic!

 

[Daveotto]

Quite annoying as the first time we were on a long drive and ended up having to divert to two different garages (first one had no air pump) to check, all the while with screaming infants in the back...

I keep a Rotring 12V powered tyre pressure gauge and pump in the boot next to the spare wheel at all times, is one thing having a TPMS but if you cant check it or easily do anything about it whats the point....never had to use it but was £20 well spent for the peace of mind should I get warnings like you have had.

 

[A3Kent]

Or get yourself one of these - http://www.halfords.com/motoring-tr...sure-gauges/michelin-high-power-tyre-inflator
I carry an older model of this in my boot at all times.

 

[S32B]

Strange that you post this! I was coming back from the Highlands last week, whilst in the middle of nowhere with no phone signal I hit a pothole that made a terrible noise . A few minutes later I got the warning on the dash! I pulled over and checked all the tyres with a little pressure gauge that I keep in the car, they were OK. I reset the pressures in the mmi and it didn't go off again. When I got home 6 hours later the pressures hadn't dropped any further, so I put it down to the pothole causing the sensor to blip.

The following day I went out and bought one of these from CostCo for £26 Amazon product tried it and it works well, now it's in the back of the car 24/7 for piece of mind.

 

[Daveotto]

The following day I went out and bought one of these from CostCo for £26 Amazon product tried it and it works well, now it's in the back of the car 24/7 for piece of mind.

The Ring one I have was a bargain form ebay and has emergency white and red lamps built in.

It is one thing the government telling manufacturers to include TPMS as an added safety feature but useless if you dont have anything in the car to react to it.

The issue with the Audi (and some other manufacturers) system is that it relies on differences in rotational speed rather than measuring actual pressure (which is more expensive, but used on BMW's) so only gives inferred pressure drop hence the blips you get after driving over potholes etc. that said it is not a bad idea to check tyre pressures after such instances

The different TPMS systems have been discussed on here in other threads

 

[h5djr]

When I had a 'blow out' on a rear tyre at around 100mph on a German autobahn a few months back my TPMS didn't react at all. It only came on after the space-saver had been fitted and even then it took some miles before it reacted. Not a system to rely on too much I think!

 

[Vertigo1]

Spent two days in North Wales a few weeks back and got a TPMS warning whilst there.

No visible sign of any of the tyres actually deflating at all but checked them all and found one of the rears was 1psi lower than the other so figured it was just a false alarm due to a slight variance or something. I had been chucking it down twisty roads so figured that might have lead to the false alarm.

Car went in the next week anyway as the aircon compressor needed replacing (yes seriously - it's six months old!) and they found one of the rears did actually have a slow puncture!

If you haven't already, I'd get all the tyre pressures checked then reset the system and see if it reoccurs. You may actually have a very slow puncture.

Incidentally, one thing I found particularly surprising and stupid was that the system doesn't tell you which wheel is suspect. Why on earth wouldn't it do that?

 

[veeeight]

It does on mine

 

[cemerson]

TPMS works great for slow punctures, but doesn't seem to react on fast/sudden ones for quite a while! It has caught a slow puncture for me before that I wouldn't have otherwise noticed, and I have had both rear tyres go completely in the past (bad luck!) and noticed myself both times before the TPMS. As with every single system in the car, it's always good to know its capabilities and limits!

 

[JohnM100]

It does on mine

Which is especially good since yours was a VCDS hack to activate it.

 

[veeeight]

It is, and it was !

Does the "standard" (non-VCDS hack) TPMS as supplied not show which tyre has lost pressure?

 

[JohnM100]

According to the manual yes but haven't tried it (deliberately or otherwise).

 

[cemerson]

Yes, I've always been told which tyre.

 

[Blackwhite]

A few months after I got my
car, I got the message that
said "loss of pressure rear right". I went to the dealer and
there was a nail in the back right tire. At the time, it was
amazing because I didn't even know it did this!

 

[Blackwhite]

A few months after I got my
car, I got the message that
said "loss of pressure rear right". I went to the dealer and
there was a nail in the back right tire. At the time, it was
amazing because I didn't even know it did this!

It showed the same message as
pictured above, except it was the
right not left.

 

[M1ke H]

TPMS has worked successfully for me on the day I had two punctures. The first was a reasonably fast loss of air, and the second a slow, less obvious loss that only came to light courtesy of the TPMS, which correctly identified the tyre in question.

Also experienced similar 'success' on the old Leon Cupra which had the same system (but without specific tyre identification).