E90Post
 


MaxcySpeed & Company
 
BMW 3-Series (E90 E92) Forum > BMW E90/E92/E93 3-series General Forums > General E90 Sedan / E91 Wagon / E92 Coupe / E93 Cabrio > DSC and DTC



Reply
 
Thread Tools Search this Thread
      01-29-2007, 12:37 PM   #1
NFS
Major General
 
NFS's Avatar
 
Drives: 335i m-sport LCI
Join Date: Jul 2006
Location: UK

Posts: 9,214
iTrader: (0)

DSC and DTC

Quote:
Originally Posted by poldim View Post
Quote:
Originally Posted by needforspeed
DTC is a lesser version of DSC ... it isn't something separate than runs alongside DSC during normal use.
I think this argument is useless and doesn't really prove anything.You here have stated that DTC is a lesser version of DSC. So that would mean that DTC is always on, then extra security measure are enable, and the entire package name changes to DSC.

Who cares what its called, so long as you don't mess with the button if you don't know what you're doing.
I'm taking this discussion out of the 'things you didn't know thread....

As you saw ... I had a bit of a set to with Norsk on the subject which strayed too far off topic.

I'm going to say again what I think is correct, disagree if you like ....

DSC is on all the time - unless you de-activate it by pressing and holding the DTC button.

It is a combination of various sensors and controls and a software programme.

The manual says this about DTC:

Quote:
Originally Posted by BMW
"Dynamic Traction Control is a version of DSC optimized for particular road conditions. It allows for a further slippage of the wheels, without totally giving up the stability control feature."
When you press the DTC button the idrive message says:

Quote:
Originally Posted by idrive
DTC activated, DSC restricted
DTC is NOT just the traction control element of DSC (as Norsk and others have said) and it is NOT 'on all the time'.

The idrive message is correct - it is activated when you press the DTC button.

If anything to 'allow further slippage of the wheels' you need to reduce the intervention of the 'traction control' element of the DSC system.

To me it seems really simple:

1. DSC is the system fully optimised for safety

2. DTC is the system optimised for low traction conditions. DSC is not off, but it is restricted as it says in the idrive message.

3. Press and hold and it all switches off.

I demonstrated this to myself last week - I engaged DTC and at 40 odd mph deliberately pushed the back end of the car wide. Traction control wouldn't have helped me, but I obviously still had some of the other parts of the DSC system because the tell-tail DSC light started flashing on the dash and the systems intervened.

BMW should have just called it DSC On, DSC Partly on and DSC off !
__________________
NFS is offline   United Kingdom
0
Reply With Quote
      01-29-2007, 12:40 PM   #2
- Paul -
Major General
 
- Paul -'s Avatar
 
Drives: see above.
Join Date: Apr 2005
Location: Yorkshire, UK

Posts: 7,253
iTrader: (5)

Garage List
2005 320D SE  [5.00]
2005 645  [4.50]
Get ready for the other views on this - ready set go!!!
__________________
- Paul - is offline   England
0
Reply With Quote
      01-29-2007, 12:43 PM   #3
NFS
Major General
 
NFS's Avatar
 
Drives: 335i m-sport LCI
Join Date: Jul 2006
Location: UK

Posts: 9,214
iTrader: (0)

Quote:
Originally Posted by 1stnewcar View Post
Get ready for the other views on this - ready set go!!!
I wanted to leave it ... but in the immortal words of Jim Moir -

'they wouldn't let it lie'
__________________
NFS is offline   United Kingdom
0
Reply With Quote
      01-29-2007, 01:04 PM   #4
Ghunger
Major
 
Ghunger's Avatar
 
Drives: 330i
Join Date: Sep 2005
Location: Seattle, WA

Posts: 1,025
iTrader: (0)

From my experience with the DSC/DTC/nothing during autocross practices, the DTC seems to limit the amount of yaw correction as well as allowing the increased wheelspin compared to DSC. It definitely allows the car to understeer without interfering.
__________________

330i Monaco Blue, Terra /w aluminum trim, SP, PP, CA, PDC, Nav, Folding Seats, Sat Prep
European Delivery Blog
Picture Gallery
Ghunger is offline   United_States
0
Reply With Quote
      01-29-2007, 01:24 PM   #5
Josh49
Major General
 
Drives: E90 325xi
Join Date: Jan 2006
Location: Boston, MA

Posts: 6,666
iTrader: (33)

Quote:
Originally Posted by Ghunger View Post
From my experience with the DSC/DTC/nothing during autocross practices, the DTC seems to limit the amount of yaw correction as well as allowing the increased wheelspin compared to DSC. It definitely allows the car to understeer without interfering.
I found in the autocross it is really helpful, necessary to turn it all off. Completely off.
__________________

E90 325XI, MYSTIC BLUE ON BLACK/ALUM, STEP, NAV, PDC, CWP, XENON, SIRIUS, ALARM, MUD GUARDS, CLEARBRA, CHROME GRILLS AND TIPS, VALENTINE 1 (HARDWIRED), HO CERAMIC 40%, 161'S, REAR FOG MOD, LUX 4.0, BLACKLINES, OEM PEDALS, MTEC FOGS, GRUPPE-M REP INTAKE. 156'S AND RUBBER MATS FOR THE WINTER.
Josh49 is offline  
0
Reply With Quote
      01-29-2007, 01:45 PM   #6
SoYank
Major General
 
SoYank's Avatar
 
Drives: 2009 E90 335i MT
Join Date: Mar 2006
Location: Brighton, Colorado

Posts: 7,460
iTrader: (1)

Garage List
Send a message via Yahoo to SoYank Send a message via Skype™ to SoYank
Quote:
Originally Posted by 1stnewcar View Post
Get ready for the other views on this - ready set go!!!
Got my welding goggles and Nomex suit standing by.
__________________
2009 E90 335i Montego Blue Black Leather Burl Walnut 6MT US Spec
SatNav ZPP ZCW 6FL TPMS iDrive PDC HWS Xenons BMW Assist Power Rear Sunshade Logic 7
European Taillights Rear Foglamp OEM Alarm PicoTray DataToys XM-DVR Multi-view Processor
Quaife ATB LSD Short Shift Knob Hartge Anti-Roll Bars AP Racing Front Brakes 19" Style 269
SoYank is offline   United_States
0
Reply With Quote
      01-29-2007, 01:49 PM   #7
RiXst3r
 
RiXst3r's Avatar
 
Drives: www.p3cars.com
Join Date: Sep 2006
Location: Ohio

Posts: 6,459
iTrader: (14)

Send a message via AIM to RiXst3r
I think this discussion is more of a "whats the difference between DSC and DTC" than a "you should turn it off if..." discussion. I think we all know what happens when its off. What we dont all know is exactly what happens when its in the different "modes" or "levels" or "DTC" or "DSC" or "DSC with DTC" or DTC with DSC" etc...
RiXst3r is offline  
0
Reply With Quote
      01-29-2007, 02:19 PM   #8
Lassaxi
Major
 
Lassaxi's Avatar
 
Drives: April ED - E90 328xi
Join Date: Nov 2006
Location: Boston

Posts: 1,035
iTrader: (0)

It's truly amazing how many times this discussion has been had. It's even more amazing how this whole discussion is simply a product of confusing marketing on BMW's part. I've refarined from chiming in until now, and I'll just say my piece and leave.

The only difference between DSC and DTC is in how the on-board control computer responds to various types of inputs. They are not separate systems. There is one system. Nothing "engages" or "disengages," and nothing "runs alongside" anything else. Talking about DTC as the "traction control part of the system" reflects that BMW has managed to confuse some of us with their marketing.

"DSC" and "DTC" are simply branded names for the software mapping that tells the car to react in different ways to the same types of external stimulus. BMW could have called it "DSC" and "Reduced DSC," or "Better Stability" and "More wheelspin," or something truly ridiculous like "airplane" and "kite." The name is just a marketing tool.

"DSC" is a program that is optimized for stability. It will allow less wheelspin than DTC, and its tolerance for unanticipated body movements is lower than DTC's.

"DTC" is a program that is optimized for moving you forward in extremely slippery conditions. It has higher tolerances for wheelsipn and body movements, because BMW knows that you have to have some amount of wheelsipn and body movement for a car to get going in snow and ice. However, it does not completely ignore wheelspin or body movement- it is simply willing to accept more of each before it reacts, and, under some circumstances, its reaction may be less aggressive than it would be under the "DSC" program.

Also, the interplay between wheelspin and oversteer in an RWD car is at least partly to blame for why the car oversteers more in DTC mode than DSC mode. Obviously, the more wheelspin that is allowed in a RWD car, the more likely it is that the rear end will break loose. The car only has a finite number of ways to respond to wheelspin and body movement. Without xDrive, its only opitions are brake one or more wheels, and reduce engine power. Within those constraints, it's not possible to allow significantly more wheelspin and completely nix oversteer at the same time. This is because the way the system nixes oversteer is by braking one or more wheels and/or reducing engine power. Coincidentally, those corrections also tend to reduce wheelspin. If you raise the threshold for responding to wheelspin, you will, on a certain level, also have to raise the threshold for responding to oversteer.
Lassaxi is offline   United_States
0
Reply With Quote
      01-29-2007, 02:22 PM   #9
shimshimhada
Brigadier General
 
shimshimhada's Avatar
 
Drives: Portal
Join Date: Jul 2005
Location: Portal

Posts: 4,840
iTrader: (2)

I also read that over 4Xmph, DSC automatically intervenes (if you had DTC enabled).
shimshimhada is offline   United_States
0
Reply With Quote
      01-29-2007, 05:38 PM   #10
Jaws
Lieutenant Colonel
 
Jaws's Avatar
 
Drives: 2006 325i mt
Join Date: Aug 2006
Location: Edmonton

Posts: 1,736
iTrader: (0)

Quote:
Originally Posted by Lassaxi View Post
It's truly amazing how many times this discussion has been had. It's even more amazing how this whole discussion is simply a product of confusing marketing on BMW's part. I've refarined from chiming in until now, and I'll just say my piece and leave.

The only difference between DSC and DTC is in how the on-board control computer responds to various types of inputs. They are not separate systems. There is one system. Nothing "engages" or "disengages," and nothing "runs alongside" anything else. Talking about DTC as the "traction control part of the system" reflects that BMW has managed to confuse some of us with their marketing.

"DSC" and "DTC" are simply branded names for the software mapping that tells the car to react in different ways to the same types of external stimulus. BMW could have called it "DSC" and "Reduced DSC," or "Better Stability" and "More wheelspin," or something truly ridiculous like "airplane" and "kite." The name is just a marketing tool.

"DSC" is a program that is optimized for stability. It will allow less wheelspin than DTC, and its tolerance for unanticipated body movements is lower than DTC's.

"DTC" is a program that is optimized for moving you forward in extremely slippery conditions. It has higher tolerances for wheelsipn and body movements, because BMW knows that you have to have some amount of wheelsipn and body movement for a car to get going in snow and ice. However, it does not completely ignore wheelspin or body movement- it is simply willing to accept more of each before it reacts, and, under some circumstances, its reaction may be less aggressive than it would be under the "DSC" program.

Also, the interplay between wheelspin and oversteer in an RWD car is at least partly to blame for why the car oversteers more in DTC mode than DSC mode. Obviously, the more wheelspin that is allowed in a RWD car, the more likely it is that the rear end will break loose. The car only has a finite number of ways to respond to wheelspin and body movement. Without xDrive, its only opitions are brake one or more wheels, and reduce engine power. Within those constraints, it's not possible to allow significantly more wheelspin and completely nix oversteer at the same time. This is because the way the system nixes oversteer is by braking one or more wheels and/or reducing engine power. Coincidentally, those corrections also tend to reduce wheelspin. If you raise the threshold for responding to wheelspin, you will, on a certain level, also have to raise the threshold for responding to oversteer.
Good post
__________________
2006 325i - Sparkling Graphite
2000 S2000 - New Formula Red
2007 Chev Silverado crew cab Z71
Jaws is offline   Canada
0
Reply With Quote
      01-29-2007, 10:38 PM   #11
FirstClass
Brigadier General
 
Drives: 328xi
Join Date: Oct 2006
Location: Pittsburgh, PA

Posts: 3,199
iTrader: (0)

Why do you guys care so much? There have been literally dozens of threads on this subject. I can summarize them all in 3 lines that follow.

Normal mode: Safe driving and boring.
DTC: Let things get a little fun.
All off: How the car was meant to be driven, experts only, craploads of fun. :rocks:
__________________
328xi Coupe, Montego Blue on Black with Alum, Step, Sport, Premium, CA, PDC, Cold Weather (Damn Pennsylvania winters)
Current Mods: Heavy right foot - Planned Mods: Lightweight right foot

Quote:
Originally Posted by jh valley View Post
shit, if i had that kind of money id buy a gtstreet for monday, an ascari a10 for tuesday, a DBS for wednesday and id just ride jessica alba the rest of the week.
FirstClass is offline  
0
Reply With Quote
      01-29-2007, 11:10 PM   #12
ages944
Captain
 
ages944's Avatar
 
Drives: E90 325i
Join Date: Dec 2005
Location: Chicago 'burbs

Posts: 990
iTrader: (0)

Cripes, yeah everyone seems to get confused about this. Makes me worry for my generation. Go out in the snow and the differences in the settings become obvious.

DSC - full intervention
DTC - medium intervention
Off - no intervention
__________________
BMW : Sine qua non

Mods: Blacklines | Rear Seat Power Outlets | Rear Fog Lights | Ashtray Garage Door Opener
ages944 is offline   Poland
0
Reply With Quote
      01-29-2007, 11:17 PM   #13
Jaws
Lieutenant Colonel
 
Jaws's Avatar
 
Drives: 2006 325i mt
Join Date: Aug 2006
Location: Edmonton

Posts: 1,736
iTrader: (0)

Quote:
Originally Posted by ages944 View Post
Cripes, yeah everyone seems to get confused about this. Makes me worry for my generation. Go out in the snow and the differences in the settings become obvious.

DSC - full intervention
DTC - medium intervention
Off - no intervention
Everyone understands what pushing the buttons does, it's the nomenclature that's in question. Even BMW themselves seem to send out contradictory messages.

I received a copy of BMW Magazine today...

Quote:
A quick jab on the Dynamic Stability Control (DSC) button before starting the climb will also activate Dynamic Traction Control (DTC)....
__________________
2006 325i - Sparkling Graphite
2000 S2000 - New Formula Red
2007 Chev Silverado crew cab Z71
Jaws is offline   Canada
0
Reply With Quote
      01-29-2007, 11:35 PM   #14
ages944
Captain
 
ages944's Avatar
 
Drives: E90 325i
Join Date: Dec 2005
Location: Chicago 'burbs

Posts: 990
iTrader: (0)

Quote:
Originally Posted by Jaws View Post
Everyone understands what pushing the buttons does, it's the nomenclature that's in question. Even BMW themselves seem to send out contradictory messages.

I received a copy of BMW Magazine today...
... could have fooled me. I see a lot of ppl asking what each of them does.


I agree though that the nomenclature could be a little clearer (eg Normal, Sport, & Off make the most sense to me ), but even the current settings aren't all that confusing. Given when you are intended to use DTC, the name Dynamic Traction Control makes sense. It's supposed to be a dynamic version of traction control. Since traditional traction control is supposed to limit wheelspin, then a Dynamic version of that traction control would allow for some more wheelspin... I know the logic seems a bit backwards, but it does make sense. I noticed German logic is like that sometimes. Heck, their language is like that somewhat often
__________________
BMW : Sine qua non

Mods: Blacklines | Rear Seat Power Outlets | Rear Fog Lights | Ashtray Garage Door Opener
ages944 is offline   Poland
0
Reply With Quote
      01-29-2007, 11:39 PM   #15
edgarj
Captain
 
edgarj's Avatar
 
Drives: 335i e92, PROcede, Eisen-fake
Join Date: Oct 2006
Location: East Tennessee via PDX

Posts: 811
iTrader: (1)

Quote:
Originally Posted by ages944 View Post
Cripes, yeah everyone seems to get confused about this. Makes me worry for my generation. Go out in the snow and the differences in the settings become obvious.

DSC - full intervention
DTC - medium intervention
Off - no intervention
So this sums it up, right? I had no idea that this was a subject of such contention. I always kill the whole system when I'm playing out of habit from my old M-roadster that just had DSC on-off. The previous (non S54 model) just had DTC, and they renamed it when it took on the ability to control more than just throttle when the rear slipped. BMW could have been clearer about this, but I can't imagine that it's that confusing when the differences are so apparent in application. Anyway, a few lines in the manual would have resolved this nicely.
edgarj is offline   United_States
0
Reply With Quote
      01-29-2007, 11:53 PM   #16
ages944
Captain
 
ages944's Avatar
 
Drives: E90 325i
Join Date: Dec 2005
Location: Chicago 'burbs

Posts: 990
iTrader: (0)

As far as I can tell, that's about the gist of it, but think of it more in terms of time before intervention. DTC waits a bit longer than DSC does before reigning the car in.
__________________
BMW : Sine qua non

Mods: Blacklines | Rear Seat Power Outlets | Rear Fog Lights | Ashtray Garage Door Opener
ages944 is offline   Poland
0
Reply With Quote
      01-30-2007, 12:36 AM   #17
Norsk
Major
 
Norsk's Avatar
 
Drives: E90 335i
Join Date: Oct 2006
Location: Canada

Posts: 1,086
iTrader: (0)

Quote:
Originally Posted by Lassaxi View Post
It's truly amazing how many times this discussion has been had. It's even more amazing how this whole discussion is simply a product of confusing marketing on BMW's part. I've refarined from chiming in until now, and I'll just say my piece and leave.

The only difference between DSC and DTC is in how the on-board control computer responds to various types of inputs. They are not separate systems. There is one system. Nothing "engages" or "disengages," and nothing "runs alongside" anything else. Talking about DTC as the "traction control part of the system" reflects that BMW has managed to confuse some of us with their marketing.

"DSC" and "DTC" are simply branded names for the software mapping that tells the car to react in different ways to the same types of external stimulus. BMW could have called it "DSC" and "Reduced DSC," or "Better Stability" and "More wheelspin," or something truly ridiculous like "airplane" and "kite." The name is just a marketing tool.

"DSC" is a program that is optimized for stability. It will allow less wheelspin than DTC, and its tolerance for unanticipated body movements is lower than DTC's.

"DTC" is a program that is optimized for moving you forward in extremely slippery conditions. It has higher tolerances for wheelsipn and body movements, because BMW knows that you have to have some amount of wheelsipn and body movement for a car to get going in snow and ice. However, it does not completely ignore wheelspin or body movement- it is simply willing to accept more of each before it reacts, and, under some circumstances, its reaction may be less aggressive than it would be under the "DSC" program.

Also, the interplay between wheelspin and oversteer in an RWD car is at least partly to blame for why the car oversteers more in DTC mode than DSC mode. Obviously, the more wheelspin that is allowed in a RWD car, the more likely it is that the rear end will break loose. The car only has a finite number of ways to respond to wheelspin and body movement. Without xDrive, its only opitions are brake one or more wheels, and reduce engine power. Within those constraints, it's not possible to allow significantly more wheelspin and completely nix oversteer at the same time. This is because the way the system nixes oversteer is by braking one or more wheels and/or reducing engine power. Coincidentally, those corrections also tend to reduce wheelspin. If you raise the threshold for responding to wheelspin, you will, on a certain level, also have to raise the threshold for responding to oversteer.

Good Post

************************************************** *******

Due to this post and the difficulty to understand German English - BMW is coming up with a simplified description on the iDrive:

DSC: Drivers with no Balls
DTC: Drivers with a Nut
OFF: Drivers with BIG BALLS



The bait has been set...
Norsk is offline   Norway
0
Reply With Quote
      01-30-2007, 04:36 AM   #18
NFS
Major General
 
NFS's Avatar
 
Drives: 335i m-sport LCI
Join Date: Jul 2006
Location: UK

Posts: 9,214
iTrader: (0)

Quote:
Originally Posted by Lassaxi View Post
"DSC" and "DTC" are simply branded names for the software mapping that tells the car to react in different ways to the same types of external stimulus. BMW could have called it "DSC" and "Reduced DSC," or "Better Stability" and "More wheelspin," or something truly ridiculous like "airplane" and "kite." The name is just a marketing tool.
Perfect - I believe that this is absolutely right.

__________________
NFS is offline   United Kingdom
0
Reply With Quote
      01-30-2007, 04:37 AM   #19
NFS
Major General
 
NFS's Avatar
 
Drives: 335i m-sport LCI
Join Date: Jul 2006
Location: UK

Posts: 9,214
iTrader: (0)

Quote:
Originally Posted by ages944 View Post
Cripes, yeah everyone seems to get confused about this. Makes me worry for my generation. Go out in the snow and the differences in the settings become obvious.

DSC - full intervention
DTC - medium intervention
Off - no intervention
This is right too ....
__________________
NFS is offline   United Kingdom
0
Reply With Quote
      01-30-2007, 04:40 AM   #20
NFS
Major General
 
NFS's Avatar
 
Drives: 335i m-sport LCI
Join Date: Jul 2006
Location: UK

Posts: 9,214
iTrader: (0)

Quote:
Originally Posted by Norsk View Post
Good Post

************************************************** *******

Due to this post and the difficulty to understand German English - BMW is coming up with a simplified description on the iDrive:

DSC: Drivers with no Balls
DTC: Drivers with a Nut
OFF: Drivers with BIG BALLS



The bait has been set...

Hang on ... you agree with Lassaxi and so do I

So what were we arguing about before ???

The only thing you were saying that I thought was wrong was that DTC was 'just' the traction control bit of DTC.

Lassaxi has it spot on when he says that DTC is just a different software map of the DSC system. By pressing the DTC button you activate that software map instead of the full DSC one.

I know from my own experience that you still get yaw control in DTC ... I don't know if it is greater or lessor, since I was trying not to crash when I tested it.

So we all agree I think
__________________
NFS is offline   United Kingdom
0
Reply With Quote
      01-30-2007, 05:33 AM   #21
- Paul -
Major General
 
- Paul -'s Avatar
 
Drives: see above.
Join Date: Apr 2005
Location: Yorkshire, UK

Posts: 7,253
iTrader: (5)

Garage List
2005 320D SE  [5.00]
2005 645  [4.50]
Got there in the end!!!
__________________
- Paul - is offline   England
0
Reply With Quote
      01-30-2007, 08:25 AM   #22
STE92VE
STEVIL Empire
 
STE92VE's Avatar
 
Drives: Fast
Join Date: May 2006
Location: Long Island, NY

Posts: 6,260
iTrader: (0)

Here's a question for you experts on DSC...Even though I'm familiar with DTC, had it on a Volvo and a TL, I will be a noob with DSC on the E92. I understand that sensors detect instability and cut power to the wheels. My question is, if you're pushing the car to it's limit and DSC activates but you don't realize it and try to compensate from the loss of power by pressing harder on the accelerator, (now for the question part) when DSC stops doing it's thing, will there be a sudden and unexpected surge to the drive wheels that might actually cause you to overcorrect and create an unpleasant experience? I know that this question will probably be answered the first time it kicks in and I'll get my first lesson on DSC, but I'm trying to gain as much knowledge as I can before I get my ride.
__________________
2007 E92 328i 6MT-Space Gray/Black Dakota/Gray Poplar w/heated seats-PCD 4/27/07 (SOLD)
2009 E90 328i xDrive 6AT-Space Gray/Oyster Dakota/Dark Burl Walnut w/ZPP,ZCW,Xenons-ED 4/17/09 - Redelivery 5/30/09 (SOLD)
2014 E84 xDrive28i 8AT-Alpine White/Black Nevada/Silver Matte w/ZMV,ZLP,494 - DD 3/14/14

STE92VE is offline   United_States
0
Reply With Quote
Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 01:26 AM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST