Once the pedal is introduced, the House at the rear of the diaphragm is reopened into the manifold, Hence the tension drops and the diaphragm falls back. Single Acting Disc Form Braking- The working of single acting disc form hydraulic braking is exactly very same as mentioned previously mentioned, https://brakeservice90009.illawiki.com/1756802/new_step_by_step_map_for_auto_brake_work