i have a DSC switch. where would the LSD and ASC switch go? *confused*

 

The LSD is only an option for the 2005 MCS/MCSC with manual transmission.
It is passive and works in the transmission to allow for maximum traction under all conditions. If traction is not maintained then DSC if ordered will kick in and work unless you turn it off at your toggle switch.

ASC is passive and there is no switch. DSC is an option that you need to order. Only DSC has a switch for manual control, otherwise for most owners it is passively on when you start your engine.

 

danke!

 

So what does the toggle switch on my '05 MCS labeled ASC do?

 

Turns it off. (Its in the owners manual)

 

Sorry for the confusion. I blame it on MINI and take none of the credit.

Your '05 MCS was ordered with no DSC. So it has a toggle for ASC and you can turn it on and off manual but this is the only case where a MINI in the US has an ASC switch.

For those that opt for DSC whether an MC or MCS you have a toggle for DSC but not one for ASC. ASC stays on when you manually turn off DSC in the Cooper S. Hence "ASC is passive there is no switch".

If you have an MC you cannot order ASC only which is a feature limited to the MCS. So no working ASC toggle possible.

 

I knew that, I just wanted to get a little bit better explanation after reading an above response.

 

Sorry but that still isn't correct. A fellow autocrosser buddy of mine used to have an 02 MCS with DSC. When he turned off DSC it also turned off ASC as he could easilly spin the front tires with no problem when leaving the line for his runs. Turning off DSC will turn off ALL traction control.

My 04' MCS and 05' MCS don't have DSC so i have an ASC switch i can turn on and off.

The LSD is a mechanical part inside your transmission that will send power to the wheel with the most traction during cornering or acceleration. So when your accelerating out of a corner and you don't have LSD you will usually "light up" or spin the inside tire, wasting energy and loosing time. An LSD will send all the power to the outside wheel and pull you out of the corner.

 

Very true about the switch. It turns off all _electronic_ traction/stability functions (both ASC and DSC), except antilock brakes.

On the subject of the limited slip differential (which is mechanical, so is unaffected by the switch setting): it will direct only a portion, not ALL, torque from the wheel with less traction to the wheel with more traction.

Dave

 

My 03 MC has a ASC switch.But I only turn it off when I have to plow through deep snow:smile:

 

Here's the unofficial answer:

All cars have ABS, which includes CBC, EBD, & MSR.
ASC+T is standard on Cooper S, and optional on all.
DSC is optional on all cars.

ASC is like "Super ABS" and includes all the systems of the standard ABS control.

DSC is like "Super ASC" and includes all the systems of ASC and thus ABS control.

Here's the official distinction between the traction control systems incorporated in the MINI, taken from BMW training textbook, "History and Introduction to the MINI":

Safe vehicle handling and braking is primarily achieved by highly developed, 'state of the art' chassis, suspension, and brakes design.
However, even on a perfectly balanced vehicle, critical situations may occur during braking, accelerating, and cornering which result in loss of directional stability.
Becasue the majority of drivers would not be able to maintain control of the vehicle in these situations, MINI has developed the following systems to assist drivers in these extreme situations:

-ABS Anti-lock braking system
---EBV Electronic Brake Force Distribution
---CBC Cornering Brake Control
---MSR Engine Drag Torque Control
-ASC Automatic Stability Control
-DSC Dynamic Stability Control

EBV, CBC, and MSR are sub-systems of, and are controlled by, the ABS system. All versions of the MINI are fitted with ABS, and thus EBV, CBC, and MSR are standard equipment [Note: EBV is also called EBD].

ASC is standard on MINI COOPER S. The ASC option is fitted as a package with ABS, CBC, and MSR systems.

DSC is not standard on any version of the MINI but is available as an option on all versions.

(skipping explanation of ABS and its sub-systems)

Automatic Stability Control + Traction (ASC+T)
The ASC system prevents the driven front wheels from spinning when engine torque is applied and maintains an equal torque distribution to both wheels. This ensures that optimum traction and directional stability are maintained. ASC is always fitted together with ABS, EBV, CBC, and MSR.
The main tasks of the ASC system are:
-To prevent loss of traction and possible resultant steering veer when engine torque is applied to the driving wheels.
-To minimize power induced understeer (front end running wide) when driving through a corner and front (driven) wheels start to slip due to excessive torque application.
Components differing from ABS system are:
-Hydraulic/Electronic Control Unit
-Interface to EMS2000 (computer)
-ASC ON/OFF switch

DYNAMIC STABILITY CONTROL (DSC)
The ABS and ASC systems sense and react purely to wheel slip (longitudinal data) but cannot sense the sideways forces (lateral data) acting on the vehicle. ASC therefore has limited influence on stability when cornering.
DSC is fitted as a package with ABS, EBV, CBC, MSR, and ASC. DSC interfaces with all these systems but, additionally, monitors the following items:
-Steering wheel movements via the steering angle sensor.
-Lateral (sideways) forces via the acceleration sensor in the DSC sensor cluster.
-Vehicle rotational speed via the yaw rate sensor in the DSC sensor cluster.

(skipping indepth info about sensors, resistance, and signal strength)

ASC SYSTEM
The ASC system, standard on the COOPER S and optional on MINI COOPER, adds to the ABS system traction control functions. The Hydraulic/Electronic Control Unit while differing from the ABS unit is similar in appearance and in the same locations as the ABS unit. Additionally, a switch is added to the central switch pack in the center console to enable the driver to turn off the ASC functions.

(diagrams...)

DSC SYSTEM
The DSC system, optional on both MINI COOPER and COOPER S, replaces either the ABS or ASC system. Additional inputs allow the DSC control unit to analyze the desired motion of the vehicle and compare it with the actual motion and if instability is detected to take corrective action.
Additional input devices used by the DSC system:
-Steering Angle Sensor
-DSC Sensor Cluster
-Hydraulic Pressure Sensor

Steering Angle Sensor
The steering wheel angle sensor is a potentiometer with two brushes positioned at 90 degrees to each other. The potentiometer provides data to the DSC control unit. When first fitted on the factory assembly line or when replaced in service, the sensor must be calibrated with the wheels in the straight ahead position. Thus, steering wheel angle is identified and analyzed by the DSC control unit.

DSC Sensor Cluster
The cluster contains a transverse acceleration sensor and a rotation speed (yaw rate) sensor. The acceleration sensor measures the lateral force acting on the vehicle when cornering. The yaw rate sensor measures the speed at which the vehicle is rotating around its vertical axis.

Hydraulic Pressure Sensor
The sensor provides fluid pressure information to the DSC control unit in the event of the driver applying the brakes during DSC intervention.

DSC Switch
The DSC switch provieds an ON/OFF request to the DSC control unit for DSC operation.

DSC Warning LED
The DSC Warning LED is located in the insrument cluster and is amber in color. The LED is on: During Pre-Drive Check, When the System is switched off by the driver, When a system fault is detected. The LED flashes when the system is active.

ASC
The system is controlled by the ASC control unit (which replaces the ABS control unit) and is permanently active when the vehicle is being driven. The driver can disable ASC through the switch panel mounted switch. ASC is fitted as standard to MINI COOPER S version and is available as a factory fitted option on all other versions of the MINI.
The prevention of wheel spin is achieved by engine torque reduction and/or brake application. To prevent one wheel spinning, brake application to that wheel is employed and to prevent both wheels spinning, engine torque reduction is employed. These processes occur within milliseconds.
The ASC control unit checks for wheel spin by comparing the speed of each front driven wheel with the speed of the rear wheel on the same side. With this information, the ASC control unit determines whether brake application or engine torque reduction is appropriate. If brake application is required, the hydraulic unit isolates the brake line to the appropriate driven wheel and hydraulic pressure is applied in that brake line until the speed of the wheel returns to a value acceptable to the control unit. The return pump that takes its fluid supply from the master cylinder reservoir provides hydraulic pressure.
If engine torque reduction is also required, the ASC control unit sends the necessary command to the Engine Management System (EMS) control unit. A torque change request from the ASC control unit takes priority over any other torque change request received by, or generated internally within, the EMS control unit. Torque reduction is limited to the minimum value necessary to prevent wheel spin. The ASC control unit constantly updates the EMS control unit to ensure that 'driver demand' for acceleration is restored as soon as conditions permit.
The ASC warning lamp in the instrument cluster will flash when the system is operating. The warning lamp is illuminated permanently if the driver has switched off the ASC system or if the ASC control unit has detected a fault with the system. The need to switch off the ASC system should only be necessary under unusual circumstances such as driving away in snow or muddy contidions. The system must be switched off when snow chains are in use.

DSC
When the lateral conrnering forces acting on the vehicle overcome the available grip on the road, understeer or oversteer will occur.
If the DSC system senses that understeer is occurring, it will apply brake force to the rear wheel that follows the inside radius of the curve thus applying a counter force which helps to bring the vehicle back onto its original course (a much lower braking force may also be applied to the front wheel on the inside of the curve). [note: this is like steering a shopping cart by stopping a rear wheel with your foot].
If the DSC system senses that oversteer is occurring, it will apply brake pressure to the front wheel that follows the outside radius of the curve. (A much lower braking force may also be applied to the rear wheel on the outside of the curve).
At the same time as with ASC, engine torque reduction will be applied.
DSC operates whether or not the driver applies the brakes and, if necessary, during ABS controlled braking.
The DSC warning lamp in the tachometer (or central mounted speedometer for USA vehicles) will flash when the system is operating. This is the same lamp and symbol as that of a vehicle equipped with the ASC system. The warning lamp is illuminated permanently if the DSC control unit has detected a fault with the system. The driver through the switch panel may disable the DSC system. When DSC is disabled, the DSC warning light is illuminated.

 

Thanks TarzanI don't tend to spin my wheels,but when driving on ice and snow,it is nice when the ASC kicks in and I then back off to regain control.
But you do have to turn it off in heavy snow conditions,the human at the wheel has more sensors,and experience to get through the drifts.
My next MINI will have DSC

 

ASC+T is standard in the Cooper model in Canada, but not available for U.S. spec Coopers.

 

Azenis, the uber street tire, get a somewhat undeserved bad rap for poor rain performance – particularly with hydroplane resistance. I've driven my 05 MCS with DSC and fresh Azenis through several torrential downpours, including 'fording' a few 'streams' in the road, with ZERO problems. It rained pretty hard here tonight, found an empty parking lot - with DSC on I had very little wheel spin, slip, or over/understeer conditions. The DSC light was on most of the time, but the car was in control.

Just a brief datapoint for anyone who's anti DSC..

 

We have discussed this before-
https://www.northamericanmotoring.co...ad.php?t=16249
Before I posted I called my MINI dealership and talked to my MA to ask the question- When DSC is turned off, is ASC still on? He said yes ASC is still on.
In the thread above check out post #32.

DSC can be turned off (hit the toggle) but if you hold down the toggle for 10 seconds you can turn off both DSC and ASC.
Can anyone confirm this from MINI???? A MINI mechanic once told me this was true but I have no confirmation.

For an MCS that has DSC, is ASC passive and at least partially on when DSC is off? Who can find out?
:smile:

 

The DSC control module REPLACES the ASC control module.

All cars come standard with the ABS control module.

If you have the ASC option, the standard ABS control module is replaced with one that still has all the features of standard ABS, but with added ASC functions.

If you have the DSC option, the standard ABS or ASC control module is replaced with one that still has all the features of standard ABS or ASC, but with added DSC functions.

The toggle switch turns ON/OFF all traction control without disabling any ABS functions.

I know the text I typed was long, but the education you receive is worth your investment in time.

P.S. Your MA was not correct, and there is no toggle/hold function of the on/off toggle.

 

I understand what you're saying. Is there anyway we can "confirm" this with MINIUSA?? I hate misinformation.

 

Like i said, i have ASC in my MCS and when its on and you try to do any kind of launch it will instantly bring to the car to a crawl. So i can assure you my friends car did not have any kind of ASC when he disabled the DSC. He could spin the front tires easily with no problem.

What Tarzan said seems to be correct.

 

We don't have to confirm this with MINIUSA. I can spin my wheels forever if I turn off DSC.

My 04 MCS has DSC...that means I don't have ASC, DSC replaces ASC but incorporates ASC as a function of DSC.

So no, if you have DSC you don't have an ABS module, an ASC module, and a DSC module...you only have a DSC module...ABS is incorporated into ASC and DSC modules if you have either one or by itself if you don't have ASC or DSC.

 

Straight from Claude Bruni (western district MINI manager):

If you have DSC you cannot turn off ASC. However, it does drastically change the point at which ASC kicks in when you turn off DSC.
To most drivers it will seem as if ASC is completely off.
There is no 2 step turn off procedure like you may find in a BMW to turn both completely off.

Also the ASC module is contained within the DSC computer box (along with several other modules).

ABS is never disabled.

 

Then i would love to see WHEN ASC finally kicks in, because i drove my friends MCS at an Autocross in the pouring rain and i could have kept my foot down and the front wheels spinning as long as i wanted with his DSC disabled.....

 

Motormouth,
Thanks for the answer from Claude Bruni.
This explains many of our observations about the ability to spin wheels when DSC is off. Also explains that for the MINI like in other BMWs the ASC is not completely off when DSC is off.

Are others satisfied with this answer or shall we look further?

 

I do not believe Claude is being responsible trying to answer your question without knowing the proper answer. He is gambling on the fact that you know less than he does.

ASC is not some magical thing that exists in the car like a soul. It is a series of wheel and torque inputs that is controlled by a special module.

MINI's are fitted with one of three modules. A regular ABS, an ASC, or a DSC. All three look similar, but there are slight differences. The unit is that aluminum block where the brake lines sprout out of in the upper left area under the hood. All three modules are a separate part number, and you can only get one.

I suspect what Claude means to say is that turning ON/OFF whatever module you have will disable all of the traction control functions of that module, but will never disable the core features of Anti-Lock Brakes (ABS). One feature of ABS is MSR (Engine Drag Torque Control), and another is CBC (Corner Braking Control).

He clearly doesn't have a true understanding of the difference, and has been able to satisfy you with that answer.

A better question for Claude would be to ask him how ASC functions could be performed in a car with a disabled DSC module. Suggest that he not answer from the hip, but research the answer for you.

 

Well, after much searching and with the help of Motormouth and Mark (with repeated emails to MINIUSA) we have the "answer" from two sources (I hope they are not the same person with aliases!)

Be it known that (and your suspicions were correct and not tricking you)
When DSC is toggled off then ASC IS OFF.

OK- no partial ASC or anything, you are on your own for what it is worth so

Go ahead and spin those wheels. Have fun. You are on full manual mode.
Enjoy the ride.

At least now we are all on the same page. My DSC is staying on for daily driving.

 

Thanks for the follow-up reply. Whom were the sources of this correct information? You might consider forwarding your findings to Claude Bruni so that he may better educate himself and others.