Abstract: A device for supplying current and/or voltage to a vehicle trailer for the electric supply of brake components of the vehicle trailer, where the vehicle trailer is connected with the tractor vehicle by a first supply line. At least one second supply line is provided to connect the vehicle trailer with the tractor vehicle. A brake light supply line may be used as the second supply line providing the current and/or voltage supply line for the electronic and/or electric components of a braking device of a vehicle trailer when the supply of the braking device has failed.

Abstract: A modified antilock system/wheel slip control system arrangement is provided whose logic provides the use of the wheel slip control system valve as the actuating valve for the compressed-air cylinder used for engaging the differential lock of a limited-slip differential. The wheel slip control system valve or actuating valve will become operative, when a wheel slip control system control operation is started or when a coefficient of adhesion difference is recognized between the right and the left driving wheel of the vehicle at a pressure below a pressure threshold which engages the differential lock, to carry out the conventional wheel slip control system brake control. Once a maximum speed is reached and the adhesion difference is minimized, the wheel slip control system valve is fully opened to engage the differential lock.