Basic Brake System Operation And Description

The hydraulic brake system consists of the following

Hydraulic Brake Master Cylinder Fluid Reservoir:

This contains the full supply of brake fluid for the hydraulic brake system. If the fluid level goes low, air will be introduced into the system and cause a soft or low brake pedal with poor stopping ability. Fix the leak and bleed the system. A soft or deformed rubber seal on underside the cap indicates contamination such as the incorrect fluid was added.  

Hydraulic Brake Master Cylinder:

Converts mechanical input force from the brake pedal into hydraulic output pressure. Hydraulic output pressure is distributed from the master cylinder through two hydraulic circuits, supplying diagonally-opposed circuits. There are seperate wheel apply circuits for the front and rear brakes. 

Hydraulic Brake Pressure Balance Control System:

This component regulates brake fluid pressure delivered to hydraulic brake wheel circuits in order to control the distribution of braking force. Pressure balance control is achieved through dynamic rear proportioning (DRP), which is a function of the ABS modulator. Refer to ABS Brakes Description and Operation for specific information on the operation of DRP.

Hydraulic Brake Pipes and Flexible Brake Hoses:

Carries brake fluid to and from hydraulic brake system components. From master cylinder to calipers and wheel cylinders. 

Hydraulic Brake Apply Components:

Converts hydraulic input pressure into mechanical output force to stop the vehicle. This includes wheel cylinders, calipers and internal ABS components. 

System Operation:

Mechanical force from the brake pedal input is converted into hydraulic pressure by the master cylinder. It is regulated to meet braking system demands by the pressure balance control system and delivered to the hydraulic brake wheel circuits by the pipes and flexible hoses. The wheel apply components then convert the hydraulic pressure back into mechanical force which presses linings against rotating brake system components such as drums and rotors. Frictions causes the wheel to slow and also causes heat which is disdipated by vents in the rotos and drums.

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