How does Traction Control work?

Soldato
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Hi all,

Please could somebody explain the basics of how Traction Control works...? and what is the difference between Traction Control and ESP?

Thanks
 
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ESP is extra sensory perception.

An example of this is that I already know this thread will start talking about how we shouldn't have any driver aids as drivers then rely upon them blah blah blah.

That's ESP.
 
Hi there

There are many types of traction control, ESP, DSC, DTC are just a few.

All the systems require ABS or certainly the better ones.

A basic traction control system detects loss of traction like say wheelspin and will just cut power, normally via cutting of the fuel supply. Wheras more advanced systems work with the ABS and can either brake each wheel independently or adjust power going to each wheel again dependent on the vehicle and system in use.

I can say that DSC on BMW's such as the new and old M5 along with even Adams 130i is a fantastic system that works very well.

Also the Corvettes have a feature called active handling and again this system really works and can save you if you enter a corner to fast and react wrongly.

However some traction control systems are useless, the one on my Mustang for example, by the time its kicked in you are either dead in a ditch or recovered it yourself.
 
I thought ESP was Electronic Stability Program?


Traction control works in exactly the same way ABS does, in reverse effect :)
 
Thank you for simplified explanation Gibbo.

You really do know quite a bit about cars ;)

Were you ever a Mechanic? or in the Motor Trade?
 
Gibbo said:
Hi there

There are many types of traction control, ESP, DSC, DTC are just a few.
In reality, though, they are only a few different types. Only four manufacturers currently build mainstream stability control systems (Continental, Bosch, Delphi, TRW) and they are all very similar amongst themselves. While there is a difference between standard ASR (TC) systems and ESC (Stability control), "standard" stability control is more or less the same across the board.

Cars fitted with features such as BMW's active steering have an added advantage in being able to turn the wheels without turning the steering wheel to the same degree. The ESC manufacturers offer systems that incorporate this in to the stability management - effectively apply opposite lock for you, if necessary.

For a really simple expalanation of the difference:

Traction control stops you wheelspinning - by reducing the torque at the drive wheels
Stability control stops you sliding - by using the TC to reduce output and the brakes (Individually) to correct direction
 
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How do you reckon that works on my A4 then?

Is that the braking kind? or the throttling back on the power kind? I ask this because sometimes it feels like im not getting full power from accelerating and other times its fine :|

Just wondering whether I should go out and get some better tyres to stick up front.

Ive got a little button on my dash to switch the ASR off but when I do press it, I dont see the little warning light come on like it says in the manual. Not sure whether the light is duff or whether it just doesnt work
 
PMKeates said:
.....snip.....

Cars fitted with features such as BMW's active steering have an added advantage in being able to turn the wheels without turning the steering wheel. The ESC manufacturers offer systems that incorporate this in to the stability management - effectively apply opposite lock for you, if necessary.

.....snip.....


How does the "Active Steering" work then???

I thought manufacturers HAD to put a physical link between the steering wheel and the steered wheels, i.e. a steering cloumn and rack, track rod ends etc.

Therefore if the wheels are turned the steering wheel will turn (and vice cersa) because there is a permanent physical link between the components.

Lots of manufacturers have a steer by wire sytem on the back burner, but NONE can fit them to production cars, because they HAVE to have this permanent physical link.

The clause for a physical link on the throttle system was only repealed recently (last ten years or so, I am not sure of the exact date off the top of my head), therefore throttle by wire systems are quite common now, the clause for steering has yet to be repealed, untill it is, it is basically illegal to fit steer by wire systems as you are suggesting.
 
I was always under the impression that active steering functioned by the rate at which the power steering pump operates is altered. For example, going slowly the pump operates at a higher rate thus giving lighter steering, and going quickly the pump rate is reduced, giving firmer and less twitchy steering.

Could be wrong though.
 
Entai said:
How does the "Active Steering" work then???

I thought manufacturers HAD to put a physical link between the steering wheel and the steered wheels, i.e. a steering cloumn and rack, track rod ends etc.

Therefore if the wheels are turned the steering wheel will turn (and vice cersa) because there is a permanent physical link between the components.
I exaggerated the point to make it easier to understand. While it isn't steer by wire, the direct connection to the wheels is through a planetary gearbox. It's essentially a variable steering ratio, so as long as the driver is making some effort to point the car in the right direction, the system can maximise that as much as it deems necessary up to its gearing limit.

Edit: I've edited my original post to avoid confusion.
 
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TweedleDum said:
I was always under the impression that active steering functioned by the rate at which the power steering pump operates is altered. For example, going slowly the pump operates at a higher rate thus giving lighter steering, and going quickly the pump rate is reduced, giving firmer and less twitchy steering.

Could be wrong though.
That's variable power assitance, which is slightly different and fitted to many many new cars :)
 
Virdi said:
Thank you for simplified explanation Gibbo.

You really do know quite a bit about cars ;)

Were you ever a Mechanic? or in the Motor Trade?

Hi there

Been surrounded by friends and family who are mechanics and engineers. My uncle is a truck mechanic for MANN, my cousin was an aircraft engineer/technician in the RAF so he is fixing things like jets etc and now he works privately I think working on commercial planes.

Since I was little always been interested in how things work and have no fear of pulling anything to bits and building it up again. I learn by reading, research, asking questions and basically just doing it and getting involved. It was exactly the same for computers for me, read some books and started playing and in the end resulted in achieving some of the worlds best overclocks and ability to diagnose and repair PCs quickly and easily. Plus I was a Wiz on DOS and Windows 3.11 :D which came naturally to me and from experience.

I aint scared to get my hands dirty and I am of the believe that if I do it myself I know I've done it properly and not cut corners or covered up any mistakes which might happen if you let someone else do it.
When its a job I aint got the tools for or its beyond my experience I goto Powerstation as I know I can trust Andy to work on my car and do things to perfection.

I have always worked on my own cars to an extent, but with the Mustang I took that extent to whole new levels. Purchasing and mapping my own ECU, datalogging the car, fitting a supercharger kit, crankshaft pulleys, larger brake kits etc. Needless to say I have never done so much to a single car before as I have with the Mustang. The experience has given me great knowledge boosted my confidence in general with working on cars. I guess the next step is pulling an engine apart. The way I think about is its all nuts and bolts that does not take rocket science to get right. :)
 
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