Originally Posted by GeorgiaHybrid (Post 196238)

Larry,

The VSC system uses the ABS system to selectively brake (or un-brake) individual wheels to stop the vehicle from getting out of control. It does use the ABS but in a different way. The ABS system stops the wheels from "locking up" under braking in slippery (ALL) conditions (snow, wet, gravel, etc.) and will continue to let you steer the car.

The VSC will brake (or un-brake) an individual wheel to limit slip angles of the car during turns. If the car has a habit of "over steering" (rear end swings out) or "understeering" (front end plows) under high speed turns, the VSC (will "attempt" to alleviate) can help eliminate those problems and let the car drive around a curve for example instead of starting to slide.

Originally Posted by GeorgiaHybrid (Post 196249)

Originally Posted by GeorgiaHybrid (Post 196249)

LOL,

Willard,

When I learned to drive we figured out how to modulate the brake pedal to prevent wheel lockup.

In the "olden" days the braking was so heavily biased to the front (mechanical brake proportioning valve) that I often had to use the rear implemented e-brake to effect "light" braking at the rear ("anchoring effect") and thereby not lose control. I also had instances with RWD wherein "light" overall braking would lock the front wheels but with rear braking still light enough that the automatic transmission could still turn the rears even so slowly.

The only answer being to shift the tranny into neutral.

I have had the ABS help in slippery conditions but never used it "in the dry". You are correct though that ABS will help under all conditions.

Well, NO...!

What about the circumstances wherein there is no loss of control threat, no plowing/understearing or skidding/overstearing, and yet ABS activates thereby simply elongating your stopping distance/time.

It is those times, and there are MANY of them, that VSC could be used to hold off ABS unless the vehicle is not following the desired path.

A skilled driver however can often benefit from the ABS system being turned off under certain extreme conditions as well as turning off the VSC system (gravel or icy conditions come to mind)

In my '92 Jeep I would remove the ABS pumpmotor fuse during the summer months. Nowadays with so many other functions dependent on the ABS pumpmotor that is no longer an option. The VSC (PSM) in my '01 911/996 has a few hundred(?) millisecond delay to give me time to react to a yaw condition.

The VSC will also brake or un-brake as required to help a driver get a car back under control. It will NOT however protect an idiot from doing something stupid and wrecking their car so you are correct in the "attempt" to alleviate a slide condition before it becomes a problem.

I guess I was trying to keep things as simple as possible as I get accused of giving people too much information at work all of the time....