Today's ABS sytems for commercial vehicles and trailers reflect specific solutions for individual vehicle model wiring and control features. In addition, the chassis mounting requirements for trailer applications uses a separate sealed housing for the relay and other sensitive components.A logical progression of design development resulted in the new ABS 6S/4K open system with the ability of being adaptable to specific vehicle control requirements. A variety of different component arrangements can be accommodated. Accordingly, it does not require a standard wiring harness. Wiring is left optional for the specific vehicle configuration. The housing may be frame mounted without any special protection and therefore can cover both trailer and tractor applications. The housing is designed to provide necessary protection from water and dirt.The electronic senses the peripheral component configuration via a simple “learning” procedure. If one of the pre-programmed configurations as listed below is detected, it is retained in a nonvolatile storage location. Redundant storage makes it possible to recover from a partial loss. If no valid mode is established, the ECU searches all identified portions by blinking out the respektive identification codes in ascending order. Once an operating mode has been established it cannot be accidentally altered as a result of component malfunction and all future diagnostic error messages refer to the original “learned” configuration.The ECU allows the following modes of operation: 2S/1K, 2S/2K, 4S/2K, 4S/3K, 4S/4K, 6S/3K and 6S/4K. Both 12 and 24 volt vehicle electrical systems are supported. An interface is provided to modify internal, nonvolatile parameters to facilitate application of the ECU for control strategies in tractor as well as trailer operation.