The brake system is used to keep the speed of the moving vehicle constant,slow down, stop it and fix it while parked. Heavy vehicles often have an air assisted hydraulic brake system. In our country, all parts used in the braking systemof passenger and cargo vehicles traveling in road traffic should be produced inaccordance with the "Type Approval Regulation (71/320/AT) [1] on the BrakingArrangements of Certain Motor Vehicle Classes and Trailers" and they should beused and their inspection tests should be carried out in legal periods by authorizedinspection institutions. In the brake systems of heavy vehicles such as Trucks,Trailers, Trailers, Semi-Trailers, Buses, load adjusting valves called ALB areused, which increase or decrease the rear brake forces of the vehicle according tothe load of the vehicle. ALB can be used mechanically or pneumatically in heavyvehicles. In this study, a test device was designed by using the microcontrollercard, pressure sensor, LCD screen in order to make the test alone, without performing help, and to increase the reliability of the test, by the operator performingthe pneumatic ALB test. As a result of the study, it is provided that the operatorcan perform the Pneumatic ALB test alone, increase reliability, and save time andlabor