Recently got a 1999 m5 the asc indicator does not go off even if the button is pressed .Can anyone tell me why? thanks

The fact that the ABS is OK means that the wheel speed sensors are OK. The sensors are the part of the system that get the most abuse, so it is good to eliminate them as suspects.
On a 1999, I think that you have a mechanical (cable-driven) throttle rather than drive-by-wire throttle. If so, the ASC has its own throttle just outboard of the regular throttle. If you don't see it, follow the air tube up from the air filter to the intake manifold. The throttle(s) are attached to the center of the intake manifold at the end of that air tube..
If your ASC has its own throttle, that means that you have an actuator and a little throttle cable running from the actuator to the ASC throttle. Since that is a moving part, it is subject to wear, dirt, and corrosion that interfere with motion. That makes this system the second suspect after wheel sensors. Check that cable for fraying and a full range of motion as it pulls the lever on its throttle. Unplug the control wire to the actuator and make sure that the connections are clean and tight.
I recently had an ASC light that turned out to be a hose clamp that was installed improperly and was interfering with the motion of the throttle arm on the ASC throttle.

Automatic Stability Control , relaited to ABS system.
Car has to be diagnose at mechanic shop , unless you have equipment for it.(specific scaner,not generic OBD II)

hold the vent button until the roof has "tilted" completely, then hold the open button until the roof has opened completely. the light that reads ASC should now be green and your sunroof should operate normally.

Check to see if your brake pads and rotors are in good condition. Or if you have replaced the pads yourself and have not reset the wheel sensors this would cause the ABS Antilock Brake System light and the ASC Automatic Stability Control light to stay on as the ASC uses the ABS brakes with computer assistance to control the car

There is a fuse No.20 (15amp) in the under dash fuse panel and a 25amp circuit breaker in the under hood fuse panel that controls the top.

When your ASC light is on this is to let you know your Automatic Stability Control system is switched off press the ASC button Till light is off /ASC is on this works with your rev limiter and should stabilized your idle. If the problem persists have your throttle control unit checked as this can trigger the ASC light as well and may also activate the ABS light if not fixed

To turn off the traction control, you need to press and hold the traction control button. Normally this is located on the centre console above the gearstick and you should have one of the following;

ASC or ASC +T
DSC
finally a button with an exclamation inside a triangle with an arrow on the outside in a clockwise direction. You'll have one of these 4 buttons.

Simply pressing it once will partially turn it off - (depending if its dsc, if not dsc but asc then the system will be turned off)

If you press and hold however, the system will be fully turned off and a warning light will appear on the dash. Again this all depends on the system you have and if you need to press and hold until the light comes on the instrument cluster,or just to press once!

Hope this helps!

does the one look something like this? IIIOIII or (((O)))

this is the brake wear indicator saying that you need brake pads somewhere on the car (front or rear).

the other sounds like you either have the traction control (its a button with either DSC or ASC written on it) turned off or its showing you that it is off because you need need brake pads.

When your ASC light is on this is to let you know your Automatic Stability Control system is switched off press the ASC button Till light is off /ASC is on this works with your rev limiter and should stabilized your idle. If the problem persists have your throttle control unit checked as thi can trigger the ASC light as well and may also activate the ABS light if not fixed

there should be a button on the dash on the right hand side of the steering wheel. or next to the gearshift selector. & it will say on it asc. if you cant see the button you dont have it. hope this helps.