Quick Take Up Master Cylinder
Low drag brake systems are more fuel-efficient than standard systems because the pads are moved further away from the rotor after application. As a result, there is less drag and better fuel efficiency. In addition, the master cylinder contains a quick take-up valve to compensate for excessive pedal travel.
The quick take-up valve and a large primary chamber provide the extra fluid to compensate for the extra distance. It bypasses the seal and provides the volume necessary during the initial brake application, quickly taking up the extra space before the pads contact the rotors. When a quick take-up master cylinder is faulty, the vehicle will have a low brake pedal. The master cylinder is not providing the volume needed to take up the space between the friction material and the brake rotor.