MK20 EI ASC: Notes

Model: E46/4 

Production Dates: 6/98 to 6/99 

ASC was standard equipment on both the 1999 323i and 328i Models. The Teves - Mark 20 EI system is used for the E46. The theory/operation of the slip control system is unchanged from the previous ASC system. The major changes of the Mark 20 El are:

• The electronic control module is integrated into the hydraulic unit.
  Fig 1: Identifying MK20 EI ASC Control Module/Hydraulic Unit

  Courtesy of BMW OF NORTH AMERICA, INC.
• The throttle reduction operation is carried out through the DME activation of the MDK motor.
  Fig 2: Identifying MDK Motor

  Courtesy of BMW OF NORTH AMERICA, INC.
• The ASC control module communicates with the AGS and DME control modules over the CAN Bus.

The Mark 20 EI system includes the Cornering Brake Control (CBC) utilized in the Bosch ASC 5 system. This feature reduces pressure build-up on the inside rear brake circuit while cornering, if the threshold values for activation are exceeded.

Fig 3: Identifying Skid Control Characteristics Of MK20 ABS/ASC

Courtesy of BMW OF NORTH AMERICA, INC.