So very occasionally I'll get the traction control light come on if, say, I've pulled 2 wheels onto the verge to let someone through and pull away sharply. Does anyone know if the Haldex system should be reacting quicker than the TC, or are the 2 systems completely separate? Will the TC intervene on a rear wheel that is spinning, or would the Haldex be sorting that out? I'm pretty sure after driving in snow and ice that the 4wd is working, and I've never had TC light or wheel spin when pulling away sharply on wet tarmac. I ask only out of interest rather than because I think there is a problem. 

 

Thanks

Pretty sure the electronic diff lock that is the brake on the slipping wheel will be sorting side to side slippage and the Haldex will be dealing with sorting power delivery between front and rear.

Imagine writing the programme for the stability control involving a Haldex.

I was reading about the stability control, it's pretty amazing stuff. It seems that the TC ESC and Haldex are all working together, which makes the most sense I guess.

I was reading about the stability control, it's pretty amazing stuff. It seems that the TC ESC and Haldex are all working together, which makes the most sense I guess.

Absolutely

The Haldex has to be involved, but I would have thought also in an 'active' rather than reactive one which, to my simple brain, complicates things even more.......it not being constant drive from what I understand.

Its way too complicated for me. I get how it works between axles, but not across them...

So very occasionally I'll get the traction control light come on if, say, I've pulled 2 wheels onto the verge to let someone through and pull away sharply. Does anyone know if the Haldex system should be reacting quicker than the TC, or are the 2 systems completely separate? Will the TC intervene on a rear wheel that is spinning, or would the Haldex be sorting that out? I'm pretty sure after driving in snow and ice that the 4wd is working, and I've never had TC light or wheel spin when pulling away sharply on wet tarmac. I ask only out of interest rather than because I think there is a problem. 

 

Thanks

 

It happens.

I think it is the car telling us to behave ourselves!

Even with 4WD, if your spinning both front and back wheels on the grass then the traction control will intervene 

Its way too complicated for me. I get how it works between axles, but not across them...

It brakes the wheel that is spinning due to loss of grip to send drive to the wheel with more grip.

I've managed to get the TC light to come on briefly with ice & mud on the road, and occasionally on a hump back bridge if I start accelerating a bit too early. It is just letting you know that it's kicked in to avoid wheel spin. It was a rare event for me until this weekend. I've now got a haldex fault (confirmed with VCDS) and the TC light has been very much in evidence, and wheel spin has made an appearance for the first time :(

I found out last year that the car doesn't even know whether it's going forwards or backwards. I did last year though and finally gave up on a hill when, although the wheels were going forwards, I realised I was actually slowly going back to where I had come from - backwards .

I was reading about the stability control, it's pretty amazing stuff. It seems that the TC ESC and Haldex are all working together, which makes the most sense I guess.

 

This shows how good it is.

At the end of that clip you get offered various other test clips.....   have a look at how some other vehicles fared in similar tests. Some are down right frightening!

It's interesting that exactly the same inputs are put in with ESC on and off as it is not a human doing the swerve as can be seen at the end of the clip.
For a faurly top heavy car it has amazing stability.

Thats excellent, thanks for posting. The second one showing the wheels in slow motion is good. Im going to see if I can find a 2 and 4wd comparison...

Thats excellent, thanks for posting. The second one showing the wheels in slow motion is good. Im going to see if I can find a 2 and 4wd comparison...

 I can't imagine how a 2wd and 4wd would be much different from each other in that test as the 4wd system is designed for traction when putting the power down on low grip surfaces, it wouldn't help keeping the car stable in the event of a skid.

 

Would be interesting to see if it did make any difference though