ASC is always on ?

What kinda BMW is it?

For example in the E39....

The ASC is on all the time until you switch it off by a single press of the ASC button.  On pressing this button to switch it off this lights up the yellow triangle on the dash board. you will still have some degree of traction control on, even though you think it is off. 

Holding the button down for 10 seconds switches it off properly and again the yellow light on the dash lights up but your wheel spins/arse hanging out will be untamed completely.

If the light is on permantly on the dash it means there is a fault with the unit.  The ASC can be quite tempramental and if there is a fault the light will come on.

When the ASC kicks in to arrest wheelspin the light will come on.

If the light isn't on and you haven't switched it off are you sure you aren't just giving it too much beans?

If there is a fault with the system plugging into a diagnostic machine is the only way to tell what is exactly wrong.

 

thanks for the tip !

i will make an appointment to see them later this week .

 

T.J. wrote: Andrew - in my E39 push the botton & the light comes on, but if you keep it pushed after 10sec the light extinguishes again & you're on your own.

Thinking about it, I can't remember now.  I stand corrected.

 

Check the cable that goes to each wheel ABS sensor for damage especially at each front wheel. It is close to the inside of each tyre. It can get frayed or cut if you happened to pick up a bramble or stick that travelled between the wheel and the strut. I had this problem on an E39. ABS sensors are available on Ebay. If its on Ebay it must be selling. If its selling it must be a common failure. 

devo11 wrote: go the cheapest way and go to a half descent garage and say to them i think one of my abs sensors is gone can you have a look and wait and see what they say.

Yeah but the only way to tell if a sensor is gone is to do a diagnostic check, so the garage will do a diagnostic check and charge you for it.

A faulty sensor does not have a different electrical resistance to a working one.  The only way you (diy) can check each sensor is to check for a broken wire between the two plug holes in the socket that is in each wheel arch...after of course removing each wheel in turn and un plugging the sensor from the loom.  But you would be lucky if it is a broken wore causing your fault.

Don't think they said sensor but pump? That is the black - metally part in the engine compartment says ABS in my car and the two I have here to work on at the mo but not sure yours will say the same. You can get one from the likes of FAB in the Uk. Be carfull with e-bay china fakes as you don't wanna mess with brake parts.

If you do the job yourself then you need a pressure bleeder, WD40 for the bleed nipple, prayers that non of the nipple will sheer of, a good ring spanner for the nipples and more prayers..... alot of tea and a Haynes/Bentley manual.

HTH 

Edited by beemerchris