The problem here is that a lot of people have not read the entire thread and are confused. 95% of the answer is already written in this thread, however, not in the same post...and with the many wrong statements, there is plenty of confusion. This is what I will try to clear up in this post.
VDC is a stability control system, it uses input from each abs sensor on each wheel to determine exactly how fast each wheel is turning, and that is how it detects slip...if 1 or 2 or 3 wheels are turning at a different speed than the other wheels/wheel..and it knows exactly how much that difference is for each wheel. That way, it can apply brakes to whichever wheel the VDC computer decides in order to help correct a skid. It also uses pitch/yaw sensors to know the g-force and in term direction of the skid. All that information gets compiled to the VDC computer and it uses it's software algorythms to decide what is best for the particular situation...this includes reducing throttle as it pleases because it has full control of the electronic throttle input. How well it does it's job depends on how the software is programmed/how complex it is.
Now, because the vehicle stability control is so complex (VDC in our case), there is no way that it would not perform traction control duties of older, simpler systems when they had just traction control and no stability control. This in term means that the stability control system cannot function unless it reduces engine power as well (ie traction control). So the VDC system is indeed traction control and then some, quite a bit some actually.
According to Nissan as it seems, the VDC system gets completely disabled by the "VDC OFF" button, which makes complete sense, and it is true, all of it's skid/stability control functions no longer function so throttle is no longer reduced and brakes are no longer applied to wheels in order to aid the driver in recovering from a skid.
Nissan does however state the exceptions. ABS stays on but that system does not work unless you are using the brakes. So now, the only system left to interfere is the ABLS (Active Break Limited Slip). This system applies braking force to the faster spinning rear wheel in order to equalize speed between them, this system has nothing to do with speed input from the front wheels now, so it does not care if you are burning out or not, it only cares that one wheel is not spinning much faster than the other. This may indeed seem like a big interferance, especially on base models with no LSD where the system has to apply much more brake force to the corresponding wheel in order to equalize speed. This is why in the base model, you feel that system interfere a lot more often.
The other system that cannot be turned off is Nissan's brake override. This system cuts throttle down to almost nothing if you press the brake while trying to accelerate. You can floor the gas pedal and press the brake as little as only to light up your taillights, and you are not going anywhere. So to those people that like to drive one foot on the brake one on the gas...you could easily slightly hit the brake in a corner by mistake and make your power output dissapear.
Other than those systems, the car lets you play with it as you please...I would prefer one button that turns this car into a 50s car as far as driver aids, but no newer car can do that. However, I have powerslid this car in dry, rain, and snow...and I can confirm from experiance that there is no power robbing nanny with VDC off.
Sorry for the very long and probably boring post, but I just thought I'd clarify this misunderstanding when it comes to VDC.
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