DSC vs DTC - what are the differences?

[ph001]

Hey all, just a little curious about this one. I think most of the E85 / E86 range have a 2 stage stability control system:

• Single press to disable DSC (Dynamic Stability Control) and just leave DTC enabled (Dynamic Traction Control).

• Long press to disable DSC and DTC completely

Reason I ask is that I was struggling to get up a modest incline in the recent snow as the DSC was just cutting in all the time and not letting any power to the wheels. A single press of the button to just have DTC enabled allowed my to seemingly spin the back wheels freely, which did actually help in the snow, but led me to wonder under what conditions the DTC operates and when it intervenes?

My previous understanding was that full DSC included inputs such as yaw, pitch, acceleration, steering angle and throttle position to determine (and recover) car stability. DTC loosens the reigns somewhat but I'm not sure to what extent.

Has anybody had any pant staining moments with just DTC enabled?

 

[road warrior]

I don't think I have dsc so my pants are already stained.

 

[ph001]

:lol: ...didn't realise the 4 pots didn't have it. Must just be the 6cyl models then.



"From BMW's web site:

Dynamic Traction Control (DTC) (Activated with a single press of the traction control button.):

Dynamic Traction Control (DTC) allows more wheel slip and thus a more dynamic driving style with higher wheel traction and DSC controlling stability. A small amount of spin on the drive wheels improves traction when pulling off from a standstill in snow or on loose terrain.

Dynamic Traction Control (DTC) is a sub-function of the Dynamic Stability Control (DSC) system that can be turned on and off. DTC has two major roles: to regulate traction and to enable sports-style driving while providing active stability control.

When the drive wheels start losing traction the DSC automatically begins stabilisation measures. The Dynamic Stability Control system curbs the engine output and stops slip on the wheels. In exceptional situations, however, a small amount of wheel slip can be an advantage.

When driving in deep snow, slush or on loose terrain a small amount of wheel spin improves traction. For these occasions, as well as those when the drivers want a sportier driving style, the DTC can be activated by pressing a button and this allows more slip and reduces the DSC’s curbing of the engine. The result: better traction and more thrust.

The DTC also makes driving on snow and ice-free roads more dynamic. When activated, the DTC allows sporty drivers more room to manoeuvre around curves than the Dynamic Stability Control and even permits controlled drifts. The driver retains complete control over the vehicle in every situation and the Dynamic Stability Control’s stabilising measures remain active even when the DTC is activated.

Pressing and holding the traction control button for a few seconds completely disables DSC"



My translation of this is that when I briefly press the DSC button and engage DTC, I can hit the gas and spin the rear tires as long as I stay 'relatively' straight. I can bounce off redline indefinitely if I wanted to. As soon as the rear end steps out a few degrees DSC kicks in and kills the wheel spin.

If I hold the DSC button for 5 seconds then I can spin tires as long as I want AND I can go as sideways as I want with absolutely no intervention.

Seems to me that DTC is probably the right driving mode for 99% of the time as full DSC is still lurking in the background with one eye open if need be. Maybe DSC should be re-labelled with a picture of a woman on it :fuelfire: ...runs for cover.

 

[ph001]

Maybe the best way to describe the difference is by using this analogy...

1. Start up the car, all traction modes are activated and working (you have not pushed any buttons) - This is just like taking your child to the playground and watching him/her swing on the swing and helping them down the slide, basically hovering over top of them to make sure they don't fall

2. Pressing the DSC button once - This is like taking a few steps back from your child at the park, allowing them to play on their own, BUT if they do fall off the monkey bars, you're there to catch them.

3. Pressing and holding the DSC button - This is equivalent to you being at the bar getting hammered and completely forgot you left your kid at the park.

 

[Smartbear]

Maybe the best way to describe the difference is by using this analogy...

1. Start up the car, all traction modes are activated and working (you have not pushed any buttons) - This is just like taking your child to the playground and watching him/her swing on the swing and helping them down the slide, basically hovering over top of them to make sure they don't fall

2. Pressing the DSC button once - This is like taking a few steps back from your child at the park, allowing them to play on their own, BUT if they do fall off the monkey bars, you're there to catch them.

3. Pressing and holding the DSC button - This is equivalent to you being at the bar getting hammered and completely forgot you left your kid at the park.

You forgot about number 4, when number 3 has been activated and you wake up in a field as they cut you out of the wreckage
Rob

 

[coupedan]

[ref]Smartbear[/ref],

You forgot about number 4, when number 3 has been activated and you wake up in a field as they cut you out of the wreckage
Rob

This is where I admit.. I can't remember the last time I drove with the systems fully enabled, even with the snow last week, I was sport on and DTC/DSC off..
Maybe I am a driving god :driving: (I joke of course) However I feel the Z4 (non-M) is too nannying and doesn't allow for enough slip, even with DTC on.

 

[R60BBA]

Turning traction control all the way off (long press) really isn’t that scary.

At the end of the day, before the 1990s, driving without driver aids was the norm.

My advice to you is go to an empty roundabout and turn traction off; then find out where the limit of the car is. This can also be done on track, (tbh is probably the better option).

Once you know where the limit is and are alert when driving you should be fine.

The only time I have traction control on is in the wet, or when my tyres are cold, or if I’m in traffic.

 

[ronk]

At the end of the day, before the 1990s, driving without driver aids was the norm.

150 BHP was a lot in those days as well !

 

[Z4Life]

Turning traction control all the way off (long press) really isn’t that scary.

At the end of the day, before the 1990s, driving without driver aids was the norm.

Agreed! Hold the button if you want to corner hard. The video game analogy is turn of DSC for better cornering, and turn off DTC for better acceleration. Otherwise electronic nannies will hamper your skill. The DSC is pretty bad in my 2003 Z. It turns on very early and is more noticeable than in my Honda Fit.

On a side note, I feel like driver aids, and insurance for that matter, make me a riskier driver. When the consequences of my actions are lessened I tend to push the envelope more. I really want to get a pre-cream puff Viper one of these days ha!

 

[Capa]

Can you really be arsed to turn on sport & dtc every time you get in the vehicle, even to pop down to the shops?

I know I can't...

 

[ph001]

Can you really be arsed to turn on sport & dtc every time you get in the vehicle, even to pop down to the shops?

I know I can't...

Well it's not exactly difficult but yes I know what you mean. Be great to be able to code it. I think currently it can only be done with an ECU remap.

 

[coupedan]

Can you really be arsed to turn on sport & dtc every time you get in the vehicle, even to pop down to the shops?

I know I can't...

Yes..

Routine is this,
Get in car, switch it on.
Press sport
Press and hold DTC
Sort music out and drive! :driving:

 

[R60BBA]

Can you really be arsed to turn on sport & dtc every time you get in the vehicle, even to pop down to the shops?

I know I can't...

I’m pretty sure it could be coded.

Not something I would do however.