A3 3.2 Quattro ESP warning light

[bearxxv]

Hi everyone,
I have a 2004 A3 3.2 V6 Quattro S-Line and recently the ESP warning light has been coming on intermittently. (coming on and staying on) I have had a lot of snow near me and the other day the ESP light was on from switching the engine on and when i tried to get out of garage area which has a slight hill noticed only the front wheels were driving (skidding as it was sheer ice).
I understand ESP is traction control etc but should that affect rear wheel drive on quattro? (My understanding is quattro is 4WD but only front were driving in this case)

I am planning on booking in at Audi indy specialist for diagnostics but would like to ask if anyone could kindly explain more about the ESP system and if/how it affects rear wheel drive.

Any response greatly received.

Ta

 

[edition]

Hi there,

Mine has done this in the past. Went into Audi 3 times and they never found an issue!

It did not show faults on there machine and the light did not come on when in there hands....

 

[bearxxv]

Oh dear! Need to get this sorted as i had a bit of an accident when trying to drive up a bit of a bank which was covered in snow and ice and have a nice crack in my rear bumper. (Not had problems on this hill before!) Loss of traction control and rear wheel drive possibly a factor.

Anyone else out there had a similar problem and any ideas what could be wrong?

 

[edition]

I could never tell wether the light being on effected the traction control from working as it only ever did this when it was wet or dry (not snowing) and they are pretty grippy with or without traction control!

Be interested if you find a solution though!

Are your tyres different tread levels front to back?

 

[bearxxv]

The tyres are OK all round. Had all replaced 13K ago and Audi service couple of months ago said all OK. I do have a slow puncture which i am about to have repaired in rear nearside which i noticed was pretty under inflated but even when its at correct pressure the light comes on.

 

[edition]

When has come on i have always been creeping in traffic going down hills......

 

[bearxxv]

Think i have found why rear wheels were not driving.
The Haldex Traction system is more Reactive than preventative, in that the front axle must lose traction and start to spin before the Haldex operates and sends torque to the rear axle. So, if ESP is not functioning correctly, i.e not detecting front wheel slip then the rear wheels wont come into play, or thats my understanding of it anyway!

Hopefully its just a dodgy sensor (makes sense if intermittent) and wont cost the earth to fix!

 

[J.R.]

I've also had this light stay on everytime I go on the motorway recently...But I have a 2.0 FSI. Would this be the senser then?

 

[edition]

When mine was doing it the rear wheels were being powered.....

 

[-Ju-]

I had a recent issue where I ******** up the ABS coding and although the ESP light was on, the car still had 4wd, I just had no traction control/ABS. Easy to check for 4wd in this snow as the back end loves to step out

 

[-Ju-]

I've also had this light stay on everytime I go on the motorway recently...But I have a 2.0 FSI. Would this be the senser then?

Could be mate, best to get a scan done to check for fault codes.

 

[edition]

Yeah i,ve noticed the rear end kicks out lovely in this weather!!!

 

[Dandle]

The Haldex Traction system is more Reactive than preventative, in that the front axle must lose traction and start to spin before the Haldex operates and sends torque to the rear axle. So, if ESP is not functioning correctly, i.e not detecting front wheel slip then the rear wheels wont come into play, or thats my understanding of it anyway!

Hopefully its just a dodgy sensor (makes sense if intermittent) and wont cost the earth to fix!

The system is reactive but should always be sending power to the rear if you have a throttle input. Alot of people believe that the front wheels need to loose traction for the rear wheels to get power and thats totally wrong, slip is a difference in torque between the front and rear axle not wheels spin. I recon though that you have an ABS sensor playing up as when the ABS kicks in the haldex unit will disengage drive to the rear wheels, if one sensor is broken then you will have the light on and the haldex unit wont be engaged as it doesnt know what the wheels are doing.

 

[bearxxv]

The system is reactive but should always be sending power to the rear if you have a throttle input. Alot of people believe that the front wheels need to loose traction for the rear wheels to get power and thats totally wrong, slip is a difference in torque between the front and rear axle not wheels spin. I recon though that you have an ABS sensor playing up as when the ABS kicks in the haldex unit will disengage drive to the rear wheels, if one sensor is broken then you will have the light on and the haldex unit wont be engaged as it doesnt know what the wheels are doing.

Thanks for the response Dandle,
I havent had any issues with the ABS whilst the ESP warning light has been on, i.e it still operates effectively. Does this ABS sensor that you mention only communicate with other systems i.e Haldex etc when ABS is activated and has no control over the ABS system itself?

Cheers

 

[Dandle]

A knackered ABS sensor would turn on the ESP light to let you know something isnt functioning correctly. It could be something as simple as the ABS ring on one of the hubs is really dirty causing an odd indication. Unless you slam the brakes on im not sure how you would know the ABS is still working fine as it only kicks in to stop you wheels skidding, are you sure its still working.

The haldex controller takes inputs from various places including brake/ABS input, steering angle, handbrake etc. Under certain condition the unit will deactivate the clutch pack so the back wheels are not connected, when the ABS has kicked in is one of those conditions.

 

[bearxxv]

A knackered ABS sensor would turn on the ESP light to let you know something isnt functioning correctly. It could be something as simple as the ABS ring on one of the hubs is really dirty causing an odd indication. Unless you slam the brakes on im not sure how you would know the ABS is still working fine as it only kicks in to stop you wheels skidding, are you sure its still working.


The haldex controller takes inputs from various places including brake/ABS input, steering angle, handbrake etc. Under certain condition the unit will deactivate the clutch pack so the back wheels are not connected, when the ABS has kicked in is one of those conditions.

Yes sure its working as when driving in these mad conditions i have felt brake pedal kicking back to let me know ABS is kicking in. Gonna get it checked out soon and will post back with results. Cheers for the feedback!

 

[bearxxv]

Just had a thought there, i had the car in to Teesside Audi for service and rear brake discs and pads change end of October and the warning light wasnt apparent before then. I dont drive the car very regularly so havent picked up on it sooner (think it 1st came on some time in Nov although as i say only drive occasionally so cant remember exactly).

Me thinks Audi may have something to do with this....

Think i will give them a ring to see if they will check it out for free before going to indy! (ha fat chance but worth a try!)