I am doing a brake job on a 93 525i and the Bentley manual says the following on page 340-2:
On cars with Automatic Stability Control + Traction (ASC + T), special BMW service equipment is required to properly bleed the ASC+T/ABS system. For safety reasons, the brake system on cars with ASC+T must not be bled using the procedures described below.
I cannot find anywhere in the manual how to determine if my car has ASC+T. On page 300-4, it describes the method of operation for the ASC+T system but it does not give enough detail to be sure if my car has it or not.