# Traction control and ABS yellow warning lights



## Gordon Alexander (May 13, 2007)

I've had this ongong problem that no-one is able to fix - the traction control and ABS yellow warning lights inexplicably come on!! There does not seem to be any consistency - I could have just started the engine (ie. not moved), or driving on a motorway (70 - 80mph) or just nipping down the road and at any of these times the warning lights come on! Sometimes they come on after 5 mins of driving or after 3 hrs of driving or don't come on at all. The lights reset when I swtich the engine off for 10 mins or so. The Audi garage want to replace everything from the ABS sensors to the 'throttle body'(?) - ie. they don't have a clue because there is no recognisable code for the fault on their diagnosis electronics. I've even been to an independent Audi/VW 'expert' without much joy although it seems it improve for a few days after he has fiddled (last time the lights only came on when I accelerated hard but now they are back to their usual fickle self!).

Any ideas?

Cheers

PS. when these lights come on does this turn off my ABS and traction control?


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## Chip_iTT (Nov 14, 2003)

Gordon,

Welcome to the forum...

See here for warning light info

Did they check for fault codes when the lights were on?

Whereabouts are you located?


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## Gordon Alexander (May 13, 2007)

Hi Chip

The lights were on when both the Audi garage and the technical chap connected up the box of trick. They recognised there was a problem but the code was unknown.

The Adobe file you sent on faults (thanks!!) does not seem to cover my particular problem that both lights come on (but not all the time) at any time and at any speed. They only reset when I switch the engine off for about 20mins.

I live near between Maidstone and Ashford in Kent.

Thanks


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## Chip_iTT (Nov 14, 2003)

So there was a fault code....

Do you know what it was?

I thought I read that it was the ABS and ESP lights that came on... that indicates the failure of a peripheral sensor, usually a wheel sensor..

Have you had any wheel/suspension work done recently?


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## NaughTTy (Jul 9, 2003)

Usually a faulty or 'stuck' longitudinal or lateral acceleration sensor - very common fault - try a search on "ABS and ESP lights and you should find lots of answers. Will only register a fault on diagnostics if the lights are on when checked. No fault code is stored otherwise.


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## Gordon Alexander (May 13, 2007)

Hi

Yes, sorry, there was a fault code but they did not recognise the code. I have no idea what the code was. Yes, it is the ABS and ESP warning lights that come on (and stay on until I switch off the engine). I haven't had any brake of suspension work done but do need new disks and pads shortly. Can anything be done at that time?

The Audi garage thought it might be the ABS sensors (which one?) but then said it might not be.

The independent Audi/VW technician thought it was to do with the communication from the accelerator to the thottle body. Admittedly, when he took the throttle body off and cleaned it, the warning lights did not come on for a number of journeys which was an improvement as they were typcially coming on EVERY journey at that time, but then reverted back to every journey again.

At the moment the lights come on for about 60% of journeys (ie. the regularity of the lights coming on is variable).

When I get my disks/pads done, is is worth them replacing the ABS sensors?

Thanks

Gordon


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## Gordon Alexander (May 13, 2007)

Hi NaughTTy
Thanks for the tip. Will search as suggested. I am new to this site/forum - are there search facilities within this site or do you mean generally (eg. via Google)?

Thanks

G


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## R70 TTC (Nov 30, 2006)

Hi, I have had exactly the same problem recently. I had the Longitudinal Acceleration Sensor (G251) replaced approx Â£94 thanks to the advice of many on the forum but unfortunately the fault remained.

Chip_iTT reminded me that the sensor needed to be zeroed and I'm not sure the garage (Indeopendent VAG garage) did that. It is back today to be replaced as the advice they had from Audi was that they are quite fickle and they have sent a new one under warranty. So hopfully it will be replaced and zeroed and the fault will disappear. Cheers


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## Gordon Alexander (May 13, 2007)

Thanks R70 TTC

Please let me know if it works out. My TT is Y reg and well and truely out of warrenty so don't want to systematically go round replacing parts that might be the problem.

Many thanks for letting me know your experience.

G


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## R70 TTC (Nov 30, 2006)

Hi, just to let you know that I have done about 250 miles since the new sensor and I'm glad to report the lights have stayed out. Cheers


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## Gordon Alexander (May 13, 2007)

Thanks R70 TTC for the update
G


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## Pj mac (Jan 10, 2016)

Since replacing hoses and pvc valve under intake manifold and changing throttle body on my tt mk1 my tc and ads lights come on under hard acceleration but resets after restarting have I upset something?


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## Hoggy (May 8, 2002)

Pj mac said:


> Since replacing hoses and pvc valve under intake manifold and changing throttle body on my tt mk1 my tc and ads lights come on under hard acceleration but resets after restarting have I upset something?


Hi, Requires a fault scan & usually is an ABS sensor or long/latitude sensors. A scan will tell you.
Can't see how what you have done would cause it.
Hoggy.


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## StuartDB (Feb 10, 2018)

Maybe your fixes meant you can accelerate hard enough up to 50mph which triggered the fault? Vcdslite will tell you whether it is the latitudinal or longitudinal sensor. Mine was the one behind the glove box , some people reckon they are sometimes moved and simply wiggling it back in its frame sorts the issue, I bought a refurb part for £40, someone on here had a link which cut it open and repaired it.


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## Pj mac (Jan 10, 2016)

It is pulling better since replacing hoses and fitting billet pcv valve as found if tighten plastic std one clamp on pcv valve it jams valve loosen it and it leaks, no worries with ally billet, cost quite a bit more but found worth it, I do have a fault code it throws up will post it later see if anyone knows of it as can't find what it is cheers


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## ady117 (Aug 28, 2013)

Its possible that the sensor (basicly a chip) has come away from it's PCB, I removed my sensor and removed the rubber around which it's packed in and my "chip" was not attached to the PCB on three of its legs, I resoldered it and had to "zero" it out using VCDS, and all has been well for the last 2 years... i think Youtube is your friend here.


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## Pj mac (Jan 10, 2016)

Here is error code I am getting 01279 not listed in handbook I got with scanner


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## Hoggy (May 8, 2002)

Hi Pjmac, It's the longitudinal acceleration sensor, it's behind the glovebox.
Same fault pops up on mine now & again, but always clears once Ign off/on.

Hoggy.


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## Pj mac (Jan 10, 2016)

Many thanks will have a look weekend, I take it glove box has too be taken out to access, 2years ago I had abs and tc lights kept coming as I got up too 20mph after pulling my hair out bleeding brakes changing wheels sensors it turned out too be green fuses on top of battery simple, many thanks I can go straight to problem
Cheers


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## Hoggy (May 8, 2002)

Pj mac said:


> Many thanks will have a look weekend, I take it glove box has too be taken out to access, 2years ago I had abs and tc lights kept coming as I got up too 20mph after pulling my hair out bleeding brakes changing wheels sensors it turned out too be green fuses on top of battery simple, many thanks I can go straight to problem
> Cheers


Hi, I checked my green fuses but it's so inconsistent, I think I fixed it & then weeks later it's back again.
It's been off for 3 MOTs so I live with it for now.
Hoggy.


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## StuartDB (Feb 10, 2018)

Hoggy has a very light right foot 

If you accelerate WOT from 20 to 60 in 3rd gear it will appear at 50mph...

You need to use torx screwdriver to take off the glove box. I got a kit from halfords with a flexible magnetic screwdriver attachment, which was great it is about 7 screws.

Then it is mounted in a mental frame bolted to the A-Pillar? You need to disconnect the cable, remove the bracket with sensor together, then (photo first) twist the sensor out the bracket (its easier to get it out than back in again  )

Then decide
new 150? 
Refurbished 40 
or DIY repair ?


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## droopsnoot (Sep 5, 2002)

This is where it was on mine










I didn't think of removing the bracket and sensor in one go - that probably would have made it much easier to get back in as I recall having a bit of trouble doing that.


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## Pj mac (Jan 10, 2016)

Is this correct part 1j0 907 651A,


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## Hoggy (May 8, 2002)

Pj mac said:


> Is this correct part 1j0 907 651A,


Hi, Yes, that's correct. Long & Lat are both the same just positioned differently.
This may help.
https://www.ttforum.co.uk/forum/viewtopic.php?t=435953
Hoggy.


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## Skeee (Jun 9, 2009)

As per Hoggy-

http://wiki.ross-tech.com/wiki/index.php/01279

Longitudanal sensor

Scan it with VCDS and look at the MVBs (Measuring Blocks) they should read Zero plus or minus a small tolerance and with the car stationary try rocking the car a little from side to side (Lat) then front to back (Long) and you should see each sensor value go up slightly as the car rocks.

from a while back-


Skeee said:


> ............................ have a look at Select Control module, 3. ABS. Measuring Blocks 3,4, 5, and 6, whilst you operate the footbrake and rock the car front to back side to side and also turn the steering wheel, then watch all the readings change and more importantly drop back down to zero when you let go/keep still.


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