: Anyone know how traction control works



bigburban
07-24-13, 04:22 PM
Does it apply the brakes, Adjust the throttle, Etc?

theotherguyssn
07-24-13, 04:57 PM
When drive wheel slip is noted while the brake is not applied, the electronic brake control module (EBCM) will enter traction control mode.

First, the EBCM requests the engine control module (ECM) to reduce the amount of torque to the drive wheels via the serial data. The ECM reduces torque to the drive wheels by retarding spark timing and turning off fuel injectors. The ECM reports the amount torque delivered to the drive wheels via the serial data circuit.
copyright gm.

06 STS Rob
07-24-13, 05:43 PM
That being said... Why with the t/c off, does the car still have active t/c (can't power brake) Has Cadillac maitained a level of t/c even when turned off? I'm guessing a tune can eliminate this.

Dave G
07-24-13, 10:44 PM
You can thank lawyers for that. I'm not sure how many times in Competitive Driving Mode I've had the back end come around just to where I want it and 'bam' the nannies kick in. On private roads of course ;)

1BadCadSTS
07-24-13, 10:54 PM
Doesn't eliminate torque management. Need to tune that out.

carter's_sts
07-25-13, 02:48 AM
Right, but then it does apply brakes to any spinning wheels.

I once could not get up a hill that was covered with muddy snow in a Trailblazer because I had put it in 4 low, which disabled TC. I went back to 4 high and just floored it.

The throttle was adjusted for me and the brakes were automatically applied where needed at every instant. The thing slowly walked up the hill perfectly straight. I was pretty impressed.



When drive wheel slip is noted while the brake is not applied, the electronic brake control module (EBCM) will enter traction control mode.

First, the EBCM requests the engine control module (ECM) to reduce the amount of torque to the drive wheels via the serial data. The ECM reduces torque to the drive wheels by retarding spark timing and turning off fuel injectors. The ECM reports the amount torque delivered to the drive wheels via the serial data circuit.
copyright gm.

theotherguyssn
07-25-13, 01:13 PM
competitive driving mode only turns traction and stabilit trac modes down so not as sensitive i haven't tried on my own car but if you press and hold traction button down for about 10 secons will turn stabilitrac all the way off and i was assume traction is off but haven't tried to power break it with it off may want to try that. will display message cross ur dic saying stabliitrac is off also

YoungBlood_STSV
07-25-13, 01:27 PM
competitive driving mode only turns traction and stabilit trac modes down so not as sensitive i haven't tried on my own car but if you press and hold traction button down for about 10 secons will turn stabilitrac all the way off and i was assume traction is off but haven't tried to power break it with it off may want to try that. will display message cross ur dic saying stabliitrac is off also

Even with it fully off the car doesn't take well to a standing burnout. You can spin yourself out without any issues because stability control won't come save you when the back steps out; but I had the experience of the car grabbing the brakes intermittently for about 10-15 seconds while on the dyno until it totally gave up, lit up the dash like a christmas tree and allowed everything to spin 100% freely.

I believe pulling the fuses solves that problem.

As to the OP's original question: Traction Control is summed up perfectly by post #2. It retards timing and cuts fuel until you gain traction again, then feeds it back in. Stability Control grabs at individual brake rotors to keep the car in a straight line.

You can't power brake with with just TC off because you will trip the SC sensors and it will grab the rear brake on whatever side steps out (plus as I described above, the car really doesn't like when the rear tires are going much faster than the fronts, it knows you're being a hooligan)

TimmyC
07-25-13, 10:26 PM
The TC also closes the throttle when enough spin is detected. I've never noticed the brakes being applied on this car for traction control but I have felt it in stability control situations.

Power braking is not allowed in the stock file but that can easily be fixed with a tune.

Pull the ABS fuse for dyno time.