Hi, apologies if this has been asked before, i`ve seen two similar posts but no sort of definite solution. I purchased 3 new tyres on my 2017 Superb mk3 a few days ago and ever since around ever 10/15 miles my tyre pressue light indicator comes on, I have reset when stationary and engine off, it seems to stay off for another 10 or so miles before coming back on. I took it back to where I got the tyres fitted and they couln`t explain it, they said prehaps worth changing the one tyre that wasn`t originally which I have now done and the light has just come back on again after approx 10 or so miles. They said there is no sensor on the wheels. I have just returned from a friend who is a mechanic and he hooked it up and got the following error code C12950 | Tire Check indicator / Wheel loose detection - Data implausible.

He was able to wipe the code off with his computer so I have only drove 5 miles or so since, If the light comes back on would any of you knowledgeable folk have any ideas?

Thanking you in advance....

I believe the ABS sensors are responsible for the tyre pressure alerts. If they malfunction they can cause warning messages to appear on your infotainment system. 

Lots of posts dealing with these problems elsewhere on the forum. 

10 minutes ago, Gammyleg said:

I believe the ABS sensors are responsible for the tyre pressure alerts. If they malfunction they can cause warning messages to appear on your infotainment system. 

Lots of posts dealing with these problems elsewhere on the forum. 

Ok thank you for the quick response. 

Why only 3 new tyres? You should always have new tyres per axle (both fronts or both rears)

 

I suspect due to different rolling resistance the computer is getting confused

The one that didn’t need replacing was a rear tyre with only 5k on it, it’s since been replaced and the issue is still there. The light has came on again unfortunately 

17 minutes ago, JK7 said:

The one that didn’t need replacing was a rear tyre with only 5k on it, it’s since been replaced and the issue is still there. The light has came on again unfortunately 

Cool, so what I would do now is go round and write down all the pressures

 

Then in 2 days do it again and see if they are all the same, just to rule out there being a slow leak. I had this last year when I had my tyres change and it kept leaking by the valve after I tested it with a soapy spray and been fine since they resealed it.

 

If all pressures fine and remain fine then can rule out tyres

 

Next possible thing is them perhaps disturbing something electrical when changing tyres so check there’s nothing too obvious but I’d have thought you’d have more errors but worth checking fronts at least.

 

I have had fun and games getting it synced, I believe I reset tpms with the engine off, then turned on car and reset tpms again then it was alright

Hi, thank you for the in depth reply, I first brought it back to the tire fitter and they checked all the pressures as I did myself and no apparent leak, yea I think there is a gremlin somewhere in it. I’m on my way to the tire place now to hopefully get to the bottom of it.

I can’t quite remember now, but I’ve got the same system as you where it’s done via ABS instead of individual tyre sensors, does it say if a specific tyre is low like front left etc?

 

On your nav, I think it’s like car > info something around that and it should list the issue

Just thought quick one to check, if they’re directional tyres you have are they all going forward? Usually listed as “outside” probably easy mistake to make

Shows all coming up at least one side of the car that it displays rear and front

It really does not make a difference if one wheel / tyre is a little different size / circumference / total diameter / pressure because if you fit a spare wheel and reset the TPMS you should not get a warning.  As it is the 4 tyres do not need to be at the same pressure, just the TPMS set and registering.

?

Is the odd 1 tyre left on the car that much more worn than the 3 new?

?

Is the car a AWD / Haldex.  You can still have a spare on but some do not like it, CC or ACC can be disabled. 

I've had similar with one odd tyre fitted, repeated resets eventually stopped the false warnings. 

14 minutes ago, Ootohere said:

if you fit a spare wheel and reset the TPMS you should not get a warning.

what are you talking about?

additionally to TPMS warning comes restriction of cruise control

what came as reason to replace OEM -5.3% sized spare to full diameter spare wheel

-> https://www.briskoda.net/forums/topic/520234-superb-mk3-spare-wheel/#comment-5817816

 

 

Not on all cars / models.  But if it does on all Skoda Superb then good that you are here to tell people. 

 

A big difference in the Circumference / total diameter. % as you show...

Edited 17 December, 20241 yr by Ootohere

4 hours ago, Danoid said:

if they’re directional tyres

They have Arrows.

 

4 hours ago, Danoid said:

“outside”

= Asymmetrical.

 

Thanks AG Falco

 

 

Hey just a quick update. Finally got my car to my mechanic today for a service, and trying to get to the bottom of this tyre pressure light coming on (Ive worked out it comes on almost all the time after 17 miles after it's been reset) I needed two rear shocks as the old ones had burst and he thought there was a possibility this could have been the issue. He visually inspected the car while replacing the shocks and servicing the car. He ran a live diagnostic test including taking on a test drive which came back looking OK he showed me a print out of a graph which was normal looking and inspected all 4 wheel bearings which he said were all fine. 

 

I have only just completed another 17 miles and the dreaded light has come back on. I'm running out of ideas now.

If I take the car to skoda will their computer be better placed to pinpoint the fault or am I just chasing my tail?!

 

Many thanks in advance.

41 minutes ago, JK7 said:

I needed two rear shocks as the old ones had burst and he thought there was a possibility this could have been the issue

 

Not a chance in hell which makes me doubt anything else he says

 

42 minutes ago, JK7 said:

He ran a live diagnostic test including taking on a test drive which came back looking OK he showed me a print out of a graph which was normal looking

 

Was this live data of the output of all 4 wheel speed sensors?

 

Anything other than that was a waste of your time and money.

 

Have you really still not had the fault codes read even by the mechanic who dropped your trousers? There should be a fault code for one of the wheel speed sensors.

Thinking “ out of the box”: 

warning only appears after 17 miles : maybe when tyres and pressures have “ warmed up”?

Warning suggests ( at least) one tyre circumference is relatively / detectably different - only after about 17 miles- than the others.

is it possible there is something  “simple” but different about one of the tyres with respect to warming up / pressure / circumference change? For example:

- is one Nitrogen filled- others air filled?

- are they all same type/pattern/ load rating?

- is one brake binding, so warming up that disc-hub- wheel more than the others?

there may be other possibilities but the fact it doesnt show up until after a good few miles suggests that warm tyre pressures are a factor rather than cold tyre pressures?

what happens if you reset when warm after 17 miles - does it stay off when cold the next day?

 

OR, as J.R. says above ( while I was typing) - a faulty ABS wheel sensor?  
But strange it takes so many miles to detect

Edited 7 January, 20251 yr by Shuggyboatsuperb

He hadn't pulled my trousers down, he's an old friend and an experienced reputable mechanic. I had actually alerted him to the two burst shocks on leaving the car with him as another garage had told me about them as I'd left it in for a diagnostic check with them just before the holidays. To be fair I've talked to several local mechanics about the issue now and no one seems to have a clue. The error code is the one I've posted In the first post. Both mechanics just said it may have been the issue neither said that was definitely it.

Thanks for your reply. Yes all tyres are the same make and size and inflated to the exact same pressure. I've reset several times on a single trip so temperature shouldn't be an issue.

 

@Ootohere - with a spare tyre on, even after resetting the TPMS, the car still knows u have a spare tyre on because of the difference in rotational speed, and hence it disables the ACC.  Reason for this is because ACC automatically applies the brakes to manage the speed, and since the ABS sensor knows about the spare tyre - it can't "safely" regulate the stopping power for ACC.

I've personally experienced this with my Superb, when I had the spare tyre on - it would not allow me to use ACC until a full-size tyre was back on.

 

The 02-Trans module reports the following warning:-

10657 - RPM Signal from ECU

 

03-ABS module reports the following 

16401 - Tire Pressure Warning

 

 

@JK7 - Rear shocks will not impact the TPMS.

So don't fall for that one.

 

The mk3 Superb uses the ABS sensors to determine each wheel's rotational speed - this is then used by the TPMS system to determine if a wheel is over or under inflated.

If the difference (between the 4 tyres) works out to b equivalent to 4 psi more or less, then the warning will show up.

 

U say u changed 3 out of 4 tyres - even though they're all the same brand and type, and inflated to the same pressure, the older one is more worn-out than the 3 newer tyres, and hence will always rotate at a different speed

However this should not b enough to trigger the TPMS.

 

Given u've reset the TPMS, and the warning shows up after a bit of driving, there is something more sinister happening for u.

As mentioned above, the ABS sensor could b a likely suspect.  Other possibilities could b the wheel hub, or the brakes binding.

 

Either way, not a straightforward resolution for u - sorry.

3 hours ago, JR RS said:

@Ootohere - with a spare tyre on, even after resetting the TPMS, the car still knows u have a spare tyre on because of the difference in rotational speed, and hence it disables the ACC.  Reason for this is because ACC automatically applies the brakes to manage the speed, and since the ABS sensor knows about the spare tyre - it can't "safely" regulate the stopping power for ACC.

I've personally experienced this with my Superb, when I had the spare tyre on - it would not allow me to use ACC until a full-size tyre was back on.

 

The 02-Trans module reports the following warning:-

10657 - RPM Signal from ECU

 

03-ABS module reports the following 

16401 - Tire Pressure Warning

 

 

@JK7 - Rear shocks will not impact the TPMS.

So don't fall for that one.

 

The mk3 Superb uses the ABS sensors to determine each wheel's rotational speed - this is then used by the TPMS system to determine if a wheel is over or under inflated.

If the difference (between the 4 tyres) works out to b equivalent to 4 psi more or less, then the warning will show up.

 

U say u changed 3 out of 4 tyres - even though they're all the same brand and type, and inflated to the same pressure, the older one is more worn-out than the 3 newer tyres, and hence will always rotate at a different speed

However this should not b enough to trigger the TPMS.

 

Given u've reset the TPMS, and the warning shows up after a bit of driving, there is something more sinister happening for u.

As mentioned above, the ABS sensor could b a likely suspect.  Other possibilities could b the wheel hub, or the brakes binding.

 

Either way, not a straightforward resolution for u - sorry.

 

Thank you for your very detailed response. My initial thought was the possibility of the tyre that wasn't changed causing the light to come on so I did try changing it as the trye shop agreed to try it and refund if it didn't work which it turned out not to.

I'm taking it to another garage this afternoon to see if they can shed any light.

@JK7  Good that you have replies to people with so much information.

Maybe an idea from the start to actually say what your Superb 2017 is and then people might give some thought to it having ACC.  Not all do. 

 

@JR RS

Edited 9 January, 20251 yr by Ootohere

Apologies, it is a Superb SE L Executive and yes it has acc.