Advance trac question.

[PopolZ]

Does the advance trac use the front brakes to keep the front wheels from spinning or only kills the power since it`s a drive by wire????

 

[vernonator]

According to wiki "Braking is automatically applied to wheels individually, such as the outer front wheel to counter oversteer or the inner rear wheel to counter understeer. Some ESC systems also reduce engine power until control is regained. ESC does not improve a vehicle's cornering performance; instead, it helps to minimize the loss of control."

http://en.wikipedia.org/wiki/Electronic_stability_control

From my experience this is correct - when it kicks in you can feel the brakes squeeze to try and get control. First winter I had my SHO I hit a spot of black ice RIGHT as I was tapping the brakes to slow down to turn onto my street. Doing 35 and went completely sideways. I could feel the brakes occillating trying to get the slide back under control.

 

[EcoBrick Bob]

Does the advance trac use the front brakes to keep the front wheels from spinning or only kills the power since it`s a drive by wire????

Are you asking relative to WOT starts or when the road is icy?  With my Flex, I have found that when WOT starting, that the TC really doesn't slow me down, in fact, if there is an issue with too much spin or hopping ( only with the Michelin Pilot Super Sports) that the TC gets me better or equal 1/4 mi times. You can power brake these vehicles much higher than my G8's, which you can't keep from creeping when over 1400 RPM.  Had to get a stall converter  with DR's,  to get decent starts at strip with G8.. 

 

[PopolZ]

What I'm asking is, if I accelerate a little too much for the POS michelin in a straight line and I see the tcs/advance trac light blink, is the car applying the brakes for me to regain traction or will it only cut the power?

 

[EcoBrick Bob]

It is my understanding that it cuts power slightly, but certainly not much as my times are almost the same with it on or with it off.  When I ran Nitto DR's on the front, it definitely helped to have it off.

 

[PopolZ]

should've done some RTFM...

Traction control system (TCS)
The traction control system is a driver aid feature that helps your vehicle
maintain traction of the wheels, typically when driving on slippery and/or
hilly road surfaces, by detecting and controlling wheel spin.
Excessive wheel spin is controlled in two ways, which may work
separately or in tandem, engine traction control and brake traction
control. Engine traction control works to limit drive-wheel spin by
momentarily reducing engine power. Brake traction control works to limit
wheel spin by momentarily applying the brakes to the wheel that is
slipping. Traction control is most active at low speeds.
During TCS events, the stability control light in the instrument cluster
will flash.
If the TCS is activated excessively in a short period of time, the braking
portion of the system may become temporarily disabled to allow the
brakes to cool down. In this situation, the TCS will use only engine
power reduction or transfer to help control the wheels from
over-spinning. When the brakes have cooled down, the system will regain
all features. Anti-lock braking and ESC will continue to function during
the cool-down period.
The engine traction control and brake traction control system may be
deactivated in certain situations. See the Switching off AdvanceTrac

section below.


Which explains why I killed my front brakes in 6000miles... I often have a tcs light show.

 

[breeves002]

Yes it does apply the brakes along with cutting power. I can hear the ABS pump kicking in in my car when there is wheelspin. Next time its really wet out, floor it from a stop and as the wheels spin listen and you should hear a kind of grinding noise. Do you notice how the speedo shoots up, then jumps back down as the wheels are slowed down to gain traction?

If traction control engages, it cuts engine power slightly (if you're WOT, it will still try to give you as much power possible), and applies the brake to ONLY the spinning wheels. This in turn sends power to the wheel on the other side of the axle that has traction. Obviously if both are spinning it will just cut power since applying the brakes really won't help. That doesn't usually happen though unless its a RWD car with a ton of power.

The AdvanceTrac stability control (ESC) is slightly different. It cuts power as well, but it applies the brake to one or more wheel depending on where you need to go. It works by taking steering wheel input and yaw sensor input. If the steering wheel is at one angle and the yaw sensors tell the ABS computer you're moving in a different direction, the system kicks in and applies the brakes where needed to get you back on track. Depends if you're understeering or oversteering or just sliding sideways lol.

 

[PopolZ]

I've never felt/heard the brakes with the TCS. I do with the ESC though...
Anyways I'll take the habit of killing the TCS when I start the car.

 

[breeves002]

Not a huge help to have TCS on an awd car anyways. On a fwd car it's helpful for some cruddy drivers if they aren't paying attention and hit the gas too hard in wet conditions. May start going to one side and then the brake on the spinning wheel is applied and keeps them going in the direction they want.