Anti-lock brake system (ABS) and anti-lock brake system with electronic differential lock (ABS/EDL) ITT Mark 20 IE: General

Fig 1: ABS Layout

Courtesy of VOLKSWAGEN UNITED STATES, INC.

The ABS or ABS/EDL brake system is divided diagonally. Brake pedal pressure is assisted pneumatically by the vacuum brake booster.

Vehicles with ITT Mark 20 IE ABS do not have a mechanical brake pressure regulator. Specially matched software in the control module controls the rear axle brake pressure regulation.

Malfunctions of the ABS or ABS/EDL systems do not influence the brake system or the vacuum assistance. The conventional braking system remains functional even if the ABS is not operating.

Fig 2: ABS Hydraulic Unit And Control Module Part

Courtesy of VOLKSWAGEN UNITED STATES, INC.

The hydraulic unit -a- and the control module part -b- form one component. Separating the two parts is only possible when the complete component has been removed from the vehicle.

New control modules (replacement parts) are not coded and must be coded after installation.