Service brake device of a vehicle, comprising a) at least one ABS pressure control valve which is controlled for slip-regulated braking by an electronic control unit, has at least one inlet valve and one outlet valve and is arranged upstream of a pressure medium actuated brake cylinder, b) a pressure medium line which supplies the ABS pressure control valve with pressure medium between the ABS pressure control valve and a valve device arranged upstream of the ABS pressure control valve into which a pressure controlled by the valve device is feedable, wherein c) the valve device feeds a pressure derived from a reservoir pressure of a pressure medium reservoir into the pressure medium line as a function of an activation by the electronic control unit, wherein d) at least one pressure sensor for measuring the pressure in the pressure medium line is arranged in the pressure medium line between the ABS pressure control valve and the valve device, wherein the electronic control unit e) controls the inlet valve and/or the outlet valve of the ABS pressure control valve and the valve device within the course of at least one test run, in order to generate a pressure detectable by the at least one pressure sensor in the pressure medium line, characterized in that the electronic control device f) directs the inlet valve and the outlet valve of the ABS pressure control valve into the blocking position, and then g) controls the valve device in order to feed pressure derived from the pressure medium reservoir into the pressure medium line, within the course of a first test run, and then h) by evaluation of the signals supplied by the pressure sensor detects the temporal pressure profile of the pressure fed into the pressure medium line and compares said pressure profile with an expected stored pressure profile, and then i) generates an error signal in the event of a deviation, present in accordance with predetermined criteria, of the detected pressure profile from the expected stored pressure profile. a) at least one ABS pressure control valve which is controlled for slip-regulated braking by an electronic control unit, has at least one inlet valve and one outlet valve and is arranged upstream of a pressure medium actuated brake cylinder, b) a pressure medium line which supplies the ABS pressure control valve with pressure medium between the ABS pressure control valve and a valve device arranged upstream of the ABS pressure control valve into which a pressure controlled by the valve device is feedable, wherein c) the valve device feeds a pressure derived from a reservoir pressure of a pressure medium reservoir into the pressure medium line as a function of an activation by the electronic control unit, wherein d) at least one pressure sensor for measuring the pressure in the pressure medium line is arranged in the pressure medium line between the ABS pressure control valve and the valve device, wherein the electronic control unit e) controls the inlet valve and/or the outlet valve of the ABS pressure control valve and the valve device within the course of at least one test run, in order to generate a pressure detectable by the at least one pressure sensor in the pressure medium line, characterized in that the electronic control device f) directs the inlet valve and the outlet valve of the ABS pressure control valve into the blocking position, and then g) controls the valve device in order to feed pressure derived from the pressure medium reservoir into the pressure medium line, within the course of a first test run, and then h) by evaluation of the signals supplied by the pressure sensor detects the temporal pressure profile of the pressure fed into the pressure medium line and compares said pressure profile with an expected stored pressure profile, and then i) generates an error signal in the event of a deviation, present in accordance with predetermined criteria, of the detected pressure profile from the expected stored pressure profile.