Does anyone ever switch the DSC off? The love of my life is a 2006MY XK8 4.2s and I have been experimenting driving with the DSC both on and off. Now I don't know if I am imagining it but I think the car rides better with the DSC in the off position and wonder, should it actually effect the ride quality? It certainly seems less "twitchy" on the back end.
Any views guy's?
Ray

 

It shouldn't affect ride quality. I've switched mine off many times. Anytime you see "ASC" flashing in yellow on the dash, it is cutting in. With the button off, your tires will spin rather than cut power. In some ways the car is more predictable with it off, but it is intended to keep you from getting too far out of control. The car will slide in a pretty controlled manner with ASC off. I value my tires enough to keep in on most of the time anymore though. The very rare times I've taken it out in the snow (on summer tires ) I turn it off an have some fun. Mostly the kitty hibernates in the winter though.

 

Ray,

It certainly does affect ride quality. Just as pulsing can be felt through the brake pedal with ABS, DSC puts a pulsing through steering and suspension giving rise to the twitchiness you describe.

The theory is the DSC (Dynamic Stability Control) adds another level of control to the Anti-Lock Braking System, Traction Control and Yaw Control on the 4.2 models. It supersedes the simpler ASC on the earlier 4.0 models.

1. Anti-lock Braking prevents wheels from locking and skidding during emergency braking.

2. Traction Control intervenes to prevent wheel spin by automatically reducing engine power output and applying braking to individual wheels.

3. Yaw Control assesses the vehicle's direction relative to driver input and applies braking pressure to individual wheels if excessive variation is detected.

DSC supposedly masterminds the three and further tweaks individual brake pressures.

I use my XK8 throughout the winter and, with the icy roads we had in December and January, was able to compare performance of the 2005 with DSC against my 2001 XK8 with ASC. The result on the 2005 with DSC was noticeably increased pulsing from the rear brakes in situations where better progress could be achieved with a controlled slide. Switching it off was an improvement.

Graham

 

Here we go. More proof I shouldn't assume I didn't realize there was a change from ASC to DSC. I don't think I would like DSC.

 

Keith,

With the treads on those raptors you don't even need tarmac.

Graham

 

Thanks for more education, Gentlemen.

I've seen the ASC flash a few times when I got on it coming through corners. Wondered what it was. Just the car letting me know it's protecting me, eh?

 

This is one thing I haven't yet played with on the Jaguar. My old Corvette has some traction device (ASR for acceleration slip regulation) that, in my opinion, was more of a hazard than a help. If you had even a bit of tire spin on a start or if you went over railroad tracks, not only would the acceleration totally cut out but the throttle pedal would actually start pushing back! This "safety" device more than once almost resulted in serious accidents where a situation called for a quick maneuver and suddenly I had no power. I found myself turning the system off fairly regularly.

I have never yet had the DSC system kick on yet in the Jaguar (at least not to my knowledge) so I don't yet know what it actually does. But I tend to drive this car much less aggressively than the Corvette.

Doug

 

What is the difference between ASC and DSC?

Mark

 

A cynic might suggest a different button on the dashboard!

ASC uses a combination of power reduction and individual wheel braking reduction (two control elements) to reduce wheelspin in slippery conditions.

DSC adds individual wheel brake application (three control elements) to this to control oversteer/understeer.

Other manufacturers have similar sytems often called ESC (Electronic Stability Control).

You can corner faster with DSC switched off. I've found on the 4.2 it does appear to activate more than ASC did on the 4.0 when the car is driven hard.

Graham

 

Thanks Graham,

Mark

 

I actually was on damp roads on a corner and romped mine a few weeks ago. The DSC kicked in and the car felt like it "stalled." Since, I have switched it off when wanting to drive it more aggressively, and it is much more to my liking.

MC