Soldato
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- 17 Mar 2004
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Would have been good in the first vid, to try the same maneuver's with it switched off
Thank you BMW DSC!
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Would have been good in the first vid, to try the same maneuver's with it switched off
Would have been good in the first vid, to try the same maneuver's with it switched off
I did, often, hence my view
When you mean switch it off, you mean completely? As one short button press to put the DSC light permanently on won't switch it off.
Not quite. DSC monitors steering angle, brake pressure, lateral acceleration, yaw and wheel speeds to determine actual and intended direction, and makes power, brake and, in some cases, different steering inputs to regain control. ASC+T is pretty much just traction control
It also DOES work very well in poor conditions, whatever housemaster says.
Yes it will on earlier systems, it was only in the last 3 or 4 years that BMW added the 2 settings, and on the M3 it switched the TC off completely.
My car's over 7 years old and it has two settings. M3's a bit of an exception.
Not quite. DSC monitors steering angle, brake pressure, lateral acceleration, yaw and wheel speeds to determine actual and intended direction, and makes power, brake and, in some cases, different steering inputs to regain control. ASC+T is pretty much just traction control
It also DOES work very well in poor conditions, whatever housemaster says.
Do tell me, how exactly does it alter the steering input?
perhaps they've only started putting DSC on as standard on all modern models.
Active steering is only an option on BMW's, I'm nearly sure anyhow
Active steering is more recognised as a system that varies the steering response of the car according to the speed - driving slowly, it takes less turns of the steering wheel to fully turn the wheels; at high speed, it takes correspondingly less turns to change direction. Sounds like a good idea, particularly when parking or navigating around town, but a lot of people dislike it for some reason. My car doesn't have active steering but I see it's an option when speccing the car from new.Although I think the stability control does implement technology that's mentioned in the article you linked to - the car recognises if you have lost control and will adjust the steering itself to compensate.
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As NickXX and 5tephen point out - Active Steering.
An interesting quote for those who do not read the link:
Some folk said:
sounds awful, I would guess this makes the effect of turning the steering wheel unpredictable, and have the capability to pitch you right into oncoming traffic or off the road through no choice of your own. Not something I want anywhere near my car thanks very much :/
Also I guess a system like this means there is no mechanical connection between the wheel and the rack, no steering feel at all?
Also I guess a system like this means there is no mechanical connection between the wheel and the rack, no steering feel at all?
I have read that the system recognises if you have already anticipated the loss of control and if so, doesn't intervene with the steering control.
I'd love to meet the guys that develop this stuff
But even if it did intervene, it's not going to throw your car randomly off to one side. It will try to keep going in the direction it was heading before control was lost.
There is a mechanical link between the wheel and rack, but only used if the electronic one fails which is highly unlikely. So yes you're driving a car with an electronic link between wheel and rack but LOL at the 'no steering feel' comment - you've obviously never driven a reasonably recent BM
It makes the effect of turning the steering wheel predictable once you are used to it. It won't land you anywhere you don't want to be unless you drive around with your eyes closed! It would be like saying a car with an automatic gearbox could suddenly launch you in to the back of another car, or off the road, as it controls the power ratio. Active Steering is an automatic gearbox for the steering wheel. Instead of having 1 gearing ratio, the car's ratio is altered depending on speed.
Active Steering also maintains a mechanical connection between the wheel and rack through the gearset.
This should help everyone...
ASC/DSC EXPLAINED
APPLICATION:
1999-2000 E46s have ASC or DSC
2001+ E46s have DSC
FUNCTION:
ASC & DSC work with the ABS system to provide enhanced vehicle stability.
ASC - Automatic Stability Control
ASC uses speed sensors at each wheel and throttle position to improve traction by applying the rear brakes if the rear wheels spin faster than the front. It can also shut off individual fuel injectors and close the throttle valve to help maximize traction. ASC also acts as a virtual limited slip differential by detecting a spinning wheel and applying braking force to just that wheel until traction is regained. AWD models (the xi) use ASC-X which monitors all 4 wheels to provide limited slip differential effect. The ASC system also provides traction control by modulating throttle, ignition timing and braking force to maintain traction.
DSC - Dynamic Stability Control
DSC builds on the features of the ASC system. While ASC functions only during acceleration and braking, DSC functions during all driving conditions such as cornering and emergency maneuvers. Additional sensors are added to acheive this level of stability such as lateral, yaw, brake pedal, and steering angle sensors. In DSC, each of the three subsystems: ABS, ASC, and DSC have jobs to do, and these are:
ABS: Cornering Brake Control, Electronic Brake Proportioning
ASC: Brake Intervention (or ABD-Automatic Braking Differential), Drag/Drive Torque Reduction
DSC: Dynamic Brake Control, Maximum Brake Control
Let's dig deeper, shall we?
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Cornering Brake Control keeps the inside rear wheel from locking during hard cornering when it may be lifted from the road surface brought on by the car's reaction to centrifugal forces a.k.a. body roll.
Electronic Brake Proportioning uses the wheel speed sensors to maximize braking ability by controlling rear braking force bias depending on vehicle's front/rear weight load balance.
Brake Intervention acts to keep any single wheel from spinning faster than the rest. It can apply brake pressure to the affected wheel to control wheelspin. This is the virtual limited slip differential effect.
Drag Torque Reduction evaluates rear wheel lockup caused by hard decceleration or engine braking on low traction surfaces. If the rear wheels spin slower than the front, this function can open the throttle to suspend coasting and regain traction. Also, another feature of this subsystem is Drive Torque Reduction. Drive Torque Reduction acts to limit the engine's torque output during low traction situations such as snow, sand, or mud. It can reduce the throttle valve angle, retard ignition timing, and cut individual fuel injectors to do so.
Dynamic Brake Control will boost brake pressure beyond what your foot can do in emergency situations. During emergency braking, when you mash your brake pedal the floor, DBC kicks in and increases the brake pressure right to the ABS limit to produce maximum braking force and minimum stopping distance.
Maximum Brake Control functions to improve braking efficency by increasing rear brake pressure when the front wheels are at lockup and are being regulated by the ABS system.
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ASC/DSC CONTROL BUTTON
The control button on the center console is used to deactivate the ASC/DSC systems.
NOTE: On all systems, ABS IS ACTIVE AT ALL TIMES.
A indicator lamp between the tachometer and speedometer is used to show ASC/DSC status.
A flashing indicator lamp indicates the system has activated.
A steady indicator lamp indicates the system is turned off or inoperative.
On the ASC system:
Press the ASC button to disable ACS while leaving ABD active.
On rear-wheel drive DSC systems:
Press the DSC button to disable DSC while leaving ABD active.
Press and hold the DSC button for 3+ seconds and the "BRAKE" instrument panel lamp will light yellow and disable all stability/traction systems.
On all-wheel drive (xi) DSC systems:
Press the DSC button to disable DSC while leaving ADB active in maximum output mode.
On ALL systems:
Pressing the ASC/DSC button again will reactive the system. If the indicator lamp does not go out or if it should come on and stay on during driving, a component has failed and should be serviced.
WARNING: If the ABS, ASC/DSC, and BRAKE lamp should all come on during driving, do not drive the car and have it serviced immediately.
--------------------------------------------------------------------------------
These different systems all work in unison to provide a very safe and stable vehicle under almost all circumstances. Remember, physics does still apply and even our BMWs have their limits. On numerous occasions, however, I have felt the DSC system kick in on slippery surfaces and jerk the car back straight without any input from me. It is quite impressive to say the least. While some may feel that ASC/DSC limits their BMW's performance, the payoff in safety on the road is too great to gamble with. At the track... well, that's a different story...
ASC/DSC EXPLAINED
APPLICATION:
1999-2000 E46s have ASC or DSC
2001+ E46s have DSC
FUNCTION:
ASC & DSC work with the ABS system to provide enhanced vehicle stability.
ASC - Automatic Stability Control
ASC uses speed sensors at each wheel and throttle position to improve traction by applying the rear brakes if the rear wheels spin faster than the front. It can also shut off individual fuel injectors and close the throttle valve to help maximize traction. ASC also acts as a virtual limited slip differential by detecting a spinning wheel and applying braking force to just that wheel until traction is regained. AWD models (the xi) use ASC-X which monitors all 4 wheels to provide limited slip differential effect. The ASC system also provides traction control by modulating throttle, ignition timing and braking force to maintain traction.
DSC - Dynamic Stability Control
DSC builds on the features of the ASC system. While ASC functions only during acceleration and braking, DSC functions during all driving conditions such as cornering and emergency maneuvers. Additional sensors are added to acheive this level of stability such as lateral, yaw, brake pedal, and steering angle sensors. In DSC, each of the three subsystems: ABS, ASC, and DSC have jobs to do, and these are:
ABS: Cornering Brake Control, Electronic Brake Proportioning
ASC: Brake Intervention (or ABD-Automatic Braking Differential), Drag/Drive Torque Reduction
DSC: Dynamic Brake Control, Maximum Brake Control
Let's dig deeper, shall we?
--------------------------------------------------------------------------------
Cornering Brake Control keeps the inside rear wheel from locking during hard cornering when it may be lifted from the road surface brought on by the car's reaction to centrifugal forces a.k.a. body roll.
Electronic Brake Proportioning uses the wheel speed sensors to maximize braking ability by controlling rear braking force bias depending on vehicle's front/rear weight load balance.
Brake Intervention acts to keep any single wheel from spinning faster than the rest. It can apply brake pressure to the affected wheel to control wheelspin. This is the virtual limited slip differential effect.
Drag Torque Reduction evaluates rear wheel lockup caused by hard decceleration or engine braking on low traction surfaces. If the rear wheels spin slower than the front, this function can open the throttle to suspend coasting and regain traction. Also, another feature of this subsystem is Drive Torque Reduction. Drive Torque Reduction acts to limit the engine's torque output during low traction situations such as snow, sand, or mud. It can reduce the throttle valve angle, retard ignition timing, and cut individual fuel injectors to do so.
Dynamic Brake Control will boost brake pressure beyond what your foot can do in emergency situations. During emergency braking, when you mash your brake pedal the floor, DBC kicks in and increases the brake pressure right to the ABS limit to produce maximum braking force and minimum stopping distance.
Maximum Brake Control functions to improve braking efficency by increasing rear brake pressure when the front wheels are at lockup and are being regulated by the ABS system.
--------------------------------------------------------------------------------
ASC/DSC CONTROL BUTTON
The control button on the center console is used to deactivate the ASC/DSC systems.
NOTE: On all systems, ABS IS ACTIVE AT ALL TIMES.
A indicator lamp between the tachometer and speedometer is used to show ASC/DSC status.
A flashing indicator lamp indicates the system has activated.
A steady indicator lamp indicates the system is turned off or inoperative.
On the ASC system:
Press the ASC button to disable ACS while leaving ABD active.
On rear-wheel drive DSC systems:
Press the DSC button to disable DSC while leaving ABD active.
Press and hold the DSC button for 3+ seconds and the "BRAKE" instrument panel lamp will light yellow and disable all stability/traction systems.
On all-wheel drive (xi) DSC systems:
Press the DSC button to disable DSC while leaving ADB active in maximum output mode.
On ALL systems:
Pressing the ASC/DSC button again will reactive the system. If the indicator lamp does not go out or if it should come on and stay on during driving, a component has failed and should be serviced.
WARNING: If the ABS, ASC/DSC, and BRAKE lamp should all come on during driving, do not drive the car and have it serviced immediately.
--------------------------------------------------------------------------------
These different systems all work in unison to provide a very safe and stable vehicle under almost all circumstances. Remember, physics does still apply and even our BMWs have their limits. On numerous occasions, however, I have felt the DSC system kick in on slippery surfaces and jerk the car back straight without any input from me. It is quite impressive to say the least. While some may feel that ASC/DSC limits their BMW's performance, the payoff in safety on the road is too great to gamble with. At the track... well, that's a different story...
I think you'll find very few people who will go "DSC doesn't work properly - it's rubbish". Most people are shocked at how good systems like DSC are. You may not like it - that's fine. What you cannot do, however, is refute it's abilities.
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