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ASR (off) Switch - What is it?

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79K views 24 replies 15 participants last post by  another147owner 
#1 ·
Hi me again

What is the ASR (off) switch located next to the front and rear fog light switches near the gear lever?

I have looked in my car handbook but cant find any mention of it.

Cheers:rolleyes:
 
#8 ·
If you corner very hard with ASR on, and traction is lost ASR will cause a brake to be applied to restore balance. The brake that is applied will depend on which wheel loses traction. ASR when activated can be detected at lowish speeds when the road is slippery. You can feel a brake applied and the throttle retarded a little until traction is restored.

Back in 2007 I attended the Alfa experience at Thruxton when ASR was demonstrated and we all had a go with ASR on and off; there was a significant difference believe me! The test involved turning into a 2nd gear slow corner marked by cones and accelerating out, with ASR on you could feel the effect - ASR off = cones everywhere as the car understeered off course.
 
#13 ·
Hence the cones :lol: Yes I described VDC; ASR is a poor man's LSD. Correct?
ASR is traction control to prevent wheel-spin on corners and on straight roads. An LSD distributes torque in accordance with the difference in rotational speed between inner and outer wheels and while it may reduce the activation of ASR (due to better road holding while cornering) it is not an alternative in the strictest sense.

I thought my ASR was on permanently but dad drove to Halfarts behind me the other day and confirmed that she is spewing big guffs of soot like a tractor so I think I might have to lose my grease monkey cherry on an EGR cleaning op.

The difference between ASR on and off is noticeable when gunning it if you don't spin the wheels... which I have no intention of doing considering the cost of tires for the thing.

:p
 
#18 ·
Sheeet this is an old thread. But for the sake of "know" I'll reply. :D

So, ASR (Anti-Slip Regulation or Antriebsschlupfregelung) does not apply the brakes EVER, it only reduces power sent to the wheels, so they do not spin like mad on slippery surface. This system is good for you if you run into a water puddle at high speed. If ASR is off, your wheels will spin like mad due to water surface tension (forgot the name of this in english) and the car will slide off the straight path when a fast spinning front wheel leaves the puddle touches the less slippery road. If ASR is on, it will detect the wheel spin, and will throttle the engine down, so their spin speed matches the car speed. This will keep you going straight no matter which wheel touches the ground first (leaves the puddle).

"Bad" side of ASR is that it has no throttle-down limit, so it will keep throttling the engine down until wheel speed matches the car speed, which might be 0 km/h. So if you are parked on a snowy surface (or ice, mud, sand, gravel,...) and you hit the gas HARD, front wheels will start to spin like mad, ASR will kick in, and because car speed is 0 km/h, ASR will throttle down until wheel speed is 0 km/h, which will turn off your car.

That is why, when you know that wheel spin is a normal thing (like driving on snow with chains on wheels), you SHOULD turn the ASR off, and let the wheels spin.

You SHOULD keep it on if you drive fast on a rainy road, to avoid accidental lane changes if you hit a puddle at high speed. Note that if you turn it off and hit the deeper puddle you will go sideways, left or right (depending on which wheel has touched the road first) until both front wheels are on solid surface.

You CAN turn the ASR off while driving on dry roads. This will make your car accelerate from 0 km/h much quicker.

To keep your ASR working properly, and VDC in general you should:
- have all 4 tires in the same model and type
- have the same air pressure in all 4 tires

I do not know why this happens, but my 156 drives much better with ASR off. I went to the shop to ask about it, mechanic there told me this story, and said "It's normal".

Sorry for the long post. :D
 
#19 ·
Sheeet this is an old thread. But for the sake of "know" I'll reply. :D

So, ASR (Anti-Slip Regulation or Antriebsschlupfregelung) does not apply the brakes EVER, ....
Sorry, but in the interest of correctness, ASR DOES apply brakes when required.

Full description of ASR, according to elearn:

Description ASR
This system carries out all the normal anti-lock and brake distribution functions (EBD) of the ABS 5.7 with EBD and also ensures the following:
- Acceleration Slip Regulation (A.S.R.)
- engine braking torque regulation (M.S.R.)
- differential lock via action on the brakes (T.C.)

The functions are ensured by adjusting drive torque and applying a braking force to one or both drive wheels.
If one or both drive wheels tend to slip during acceleration, the control unit orders the engine control unit to reduce the torque transmitted by the engine to the wheels and almost simultaneously brakes the wheel or wheels without the driver having to do anything.
If the wheels tend to lock during hard deceleration, the ABS control unit requests the engine control unit to adjust engine braking toruqe to prevent car stability.
The system can be cut out by activating a button located on the console.
A led comes on on the button and a message is displayed on the instrument panel DOT matrix to indicate deactivation of the ASR/MSR.
The button warning light comes on and the DOT matrix message is repeated to indicate system cut-out due to a fault recorded by the control unit.
ASR/MSR intervention is indicated by the warning light on the dashboard flashing.

Each time the vehicle is started up the ASR/MSR function is activated, even if the ignition has been turned off with the function deactivated.
The system processes the signals coming from the active sensors, the brake light switch and the button for switching the A.S.R. function on/off.
It continually compares the speed of wheels on the same side of the car (Front right with Rear right - Front left with Rear left) and causes the ASR to cut in when a speed difference in excess of 2-6 km/h (cut-in threshold) is detected between wheels on the same side. The control unit turns on the MSR function when it detects an excessive difference between the front and rear axles because the front wheels tend to slow down too much compared to the rear wheels.
The ABS/ASR control unit communicates continuously with the engine control unit via the C-CAN line.
The ASR function is active under all car speed conditions. Braking action is cut out after 80 km/h.

Operating strategy

Drive wheel slippage
Intervention - intervention times in road conditions with good grip (asphalt)
Torque reduction by the engine control unit by altering ignition advance - 6/100 s after the skid threshold is exceeded;
Further torque reduction by reducing throttle opening (by the engine control unit with motorized throttle body) - after 15/100 s;
Hydraulic system intervention (braking force on drive wheel) - after 2/10 s.

Operation under conditions of poor grip
The system is able to detect this situation by comparing drive wheel acceleration with torque transmitted by the engine (engine load via engine control unit).
The system performs in the same way as when both drive wheels are in road conditions with good grip (asphalt) and the cut in thresholds are at the lower limit.

Only one drive wheel slipping.
Intervention-intervention times
Torque reduction by the engine control unit by altering ignition advances - 6/100 s after the threshold is exceeded;
Further torque reduction by reducing throttle opening (by the engine control unit with motorized throttle body) - after 15/100 s.
Effect on hydraulic system, braking action is exerted on the slipping wheel to give the differential a resistive force on the side with poor grip (T.C.)
This resistive force allows the differential to transmit an equal torque with good grip.

One wheel slipping on a bend with good grip (asphalt).
The system detects the presence of a bend from the rear wheel speed (drawn).
It implements the same intervention procedures described for when only one drive wheel is slipping; the cut-in thresholds are increased to the upper limit. The torque reduction is applied gradually.

One wheel slipping on a bend with poor grip (snow or ice).
It implements the same intervention procedures described for when only one drive wheel is slipping; the cut-in thresholds are increased to the lower limit. The torque reduction is accentuated (to ensure good car lateral containment).
 
#20 · (Edited)
On a wet, fast road with an island in the middle of it:

1) hoof it up to the island and tan it round it. Taking the second exit, bury your foot in the carpet on the accelerator as you come off the island;
2) find a route back to your starting position;
3) Press the ASR button and repeat point number 1;
4) point 2 no longer applies. at this point, you realise that point 1 should've been point 2 and point 1 should have instructed you to pack a spare pair of troosers - HA HA joke is on you and your ****ty pants.
 
#24 ·
I must admit it does feel like the ASR comes on in the dry sometimes. When it's dry it feels like you get more in second and third. Of course, doing so with it off in 1st results in rubber coating the road. I've had wheel spin with it on the wet too, although that might be related to something else.
 
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