Hydro Unit Abs/asc+t

[gjmane36]

My ABS/ASC unit is humming. The asc switch also on occassion wil not disengage. I checked Pelican Part for part numbers and cost. Pelican does not show my 1995 540ia BMW as having this part. What would make the unit hum? Is the humming a sign of defective hydro unit or is the unit just in need of repair, or is there something else that needs attention?

[shogun]

Check the fluid level
Ever changed the fluid or is it very old
change the filter
part numbers you will find here
http://www.realoem.com/bmw/select.do
and check for prices at www.autohausaz.com

[gjmane36]

Check the fluid level
Ever changed the fluid or is it very old
change the filter
part numbers you will find here
http://www.realoem.com/bmw/select.do
and check for prices at www.autohausaz.com

Thanks. I will check it out. I did figure it to be the water pump. I had just replaced the water pump, which was defective. Is it possible there is air in the system? If so, is there a procedure for removing the air?

[shogun]

Open the reservoir for Pentosin or ATF (whatever your car needs), start the engine, turn the steering wheel 3-4 times left and right till the end.
Refill the reservoir if required, end of bleeding.....