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Discussion Starter #1
I saw in the "I am sorry to report" thread that JT mentioned ABS is always on.

Little known fact - if you hold the ABS button down for three seconds, not only will you turn off the ABS, you will also turn "something" off with the brakes. The emergency brake light will show yellow (as opposed to the red when the e-brake is engaged).

I always thought this turned off the abs. Does it? Or is it something else. Perhaps this is a rtfm question, but . . .
 

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There is no ABS button. ABS stand for "Anti-Lock Brake" system.

There is either an ASC+T button (not in the US), or a DSC button.

If you hold down the DSC button for three seconds, this turns off the "Active Differential Braking" system. ADB attempts to simulate a limited slip differential by braking the wheel that begins to slip. With open diffs, this is theoretically helpful, as the diff sends the most power to the wheel with the LEAST traction.

I would STRONGLY advise against turning either one of these off if you aren't absolutely sure of what you're doing. MANY people turn the nannies off and almost immediately stuff their cars. Make sure you can control it.
 

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If you REALLY want to drive with no ABS, you can pull about four or five fuses and take out the whole system.

Edit: I would say that this would qualify as "pretty dumb" for general use on the street. I did it once... Because I wanted to see what my car drove like without ADB (xis can't disable it), but I'll never do that again.
 

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Discussion Starter #4
Oops. I meant ABS button of course. And I knew one of you guys would know what the brake portion of the switch did. Personally, I usually only turn them off on the track. At a driving school, I want to learn how to drive. The car doesn't need lessons.

On the other hand, I don't think DSC is necessary to drive a car. It's probably not a good idea to turn it off for the first time and head into a corner at full throttle, but it doesn't take a professional to drive without it. In fact, this is the first car I have ever had with DSC and the second with any kind of traction control at all . . .
 

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Meat Puppet
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In summary:

Press and release DSC button = Stability control off.
Press and Hold DSC button for 3 secs = DSC and ADB off.

In both cases ABS is on. (Unless you Start Pulling Fuses out of the fusebox)

There is no ABS button.


Driving on the streets with DSC off is not recomended.


Personally I like DSC, on the streets. Next time you're on a DRY, SAFE, constant radius corner (like a fwy onramp) try holding it to the floor. The car will accelerate to a point where the available tire grip will activate DSC. The throttle will be automatically reduced and the car will continue in the corner at the near top possible speed. (Please don't be an idiot with this test, you might want to work up to this slowly. DSC can not stop the laws
of physics, if you go into a turn too hot, bad understeer and an agricultural experience are in your future.)

My best DSC experience was one drizzling morning, as I followed an Lexus SC400 on an onramp. The weenie, had been shadowing me for blocks, and got on the ramp before me. As he passed the apex of the corner, he added a bit too much power, and suffered massive oversteer forcing the rear of his car to back into the guardrail with a nice metalic tink. With DSC, this would not of of been possible. The "extra" throttle would of been removed and he would of continued straight through the corner.

BTW, I find my Autocross times are about .3-.5 faster on a 60 sec course with ADB off.
 

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bmwdude
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This does not turn off the ABS. it only turns off the Active Braking System. You can not turn off the ABS on these cars.
 

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you know, i think that if you have DSC on a car that most people should just keep it on. but some of you guys talk about it as though it's the one thing that keeps your car from immediately being drawn into curbs and lightpoles.

you do realize that the majority of cars out there are driving... *gulp*... without DSC features. do all your second cars have DSC-like features? if i go from my E46 to my E30, does that mean i have a deathwish?

like i said, DSC is a good thing, but let's not get out of hand.

kurt
 

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bmwdude
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Perfectly said. YOu must control YOUR car. Let DSC help but not do all of the work or you are in trouble.
 

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I agree... But if you don't have any idea what the buttons do, or what they're even labelled, then you really shouldn't be pushing them.
 

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bmwdude
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Good Point. The documentation is very poor in this area. I had to talk this over with a few people that I race with. That is how I figured out how to use this effectivly myself.
 

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That's certainly true... You need a basic understanding of the mechanics of the car to figure out what they do. Unfortunately, very few people have that.
 

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OMGWTFBBQ
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mweingand said:
Good Point. The documentation is very poor in this area. I had to talk this over with a few people that I race with. That is how I figured out how to use this effectivly myself.
At the last autocross in the rain here, there was a lot of debate over whether to disable DSC (or whatever the equivalent or closest thing on their cars was). What suprised me was that they weren't newbies like me, but guys that have beend riving competitively for 20+ years and are usually in the hunt for class wins every time.

Here's hoping that it rains for tomorrow's :D
 

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Discussion Starter #14
Nick325xiT 5spd said:
I agree... But if you don't have any idea what the buttons do, or what they're even labelled, then you really shouldn't be pushing them.
Oh, give me a brake. So I used one three letter acronym instead of another when I was typing and thinking about both of them. Guess I better never push the ABS button again!! Wait, was that DSC? Wait - I better go run out and check. My driving skill depends on knowing the label.

As for what they do, well you know what? It's very easy to know what they do for car control without knowing exactly what they do mechanically. First time I used the brake button was to get the car to oversteer in the car control portion of a driving school. Guess I should have gone and done some research before I followed the advice of my instructor and benefitted from the class.

But you are right. I am massively incompetent and should never touch the button again. Especially since I had the nerve to ask what the second function was.
 

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rwg said:


Oh, give me a brake. So I used one three letter acronym instead of another when I was typing and thinking about both of them. Guess I better never push the ABS button again!! Wait, was that DSC? Wait - I better go run out and check. My driving skill depends on knowing the label.

As for what they do, well you know what? It's very easy to know what they do for car control without knowing exactly what they do mechanically. First time I used the brake button was to get the car to oversteer in the car control portion of a driving school. Guess I should have gone and done some research before I followed the advice of my instructor and benefitted from the class.

But you are right. I am massively incompetent and should never touch the button again. Especially since I had the nerve to ask what the second function was.
Look, I'm sorry if I came across in an arrogant manner. However, so far as I can tell, you still haven't figured out what the systems do. A basic mechanical understanding of WHAT the systems do tells you WHEN they will perform that function and will also tell you what you lose or gain by disabling them. To say that disabling DSC and ADB will make the car oversteer is a gross oversimplification that can get you into trouble.

And no, I don't think you should be turning off ADB until you know what it does. This does not, of course, apply to driving clinics.
 

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Meat Puppet
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rwg said:


First time I used the brake button was to get the car to oversteer in the car control portion of a driving school.
Brake button? Please tell me where to find mine. I have a DSC button, the buttons on the stereo, a few on the steering wheel, even more on the climate control, but none are labeled "brake".

Do you mean you used the parking brake handle to oversteer? Starting a turn and then pulling the parking brake does induce a little :) oversteer.... (and flat spots a good set of tires.) but can be fun in the rain.
 

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Discussion Starter #18
Nick, it was just the first comment I have ever seen you make that I thought was assinine, and it was directed at me. Of course, you don't know that I have Chicago weather experience of 4 years in a camero, 3 years in a Trans Am, and 7 years in a 240 sx - all of which had rear wheel drive and no sort of traction control at all.

The point of the post was - what does the switch do when you shut part of the brake system off? You knew the answer to that. Frankly, I don't care what the button is labeled. I push it, the dsc goes off. I hold it down for three seconds, something else happens that lets the car slide when it otherwise wouldn't.

If it mimics a lsd, it sounds like something to leave on during normal track time - something else I did not know. Learning this stuff is why I come to the board. Having someone say "you shouldn't push that button b/c you called it an ABS button" is not.
 
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