Brake application

The brakes are applied through the ESP control module governing the pump motor, the pressure increase and pressure relief valves, and the inlet and outlet valves in the hydraulic unit so that the braking force on each wheel can be controlled individually. The ESP control module receives information on the brake pressure from the brake pressure sensor. This information is used to control the braking force on each wheel to correspond to the braking force applied by the driver. An ESP regulated wheel is controlled using the ESP criteria.

Both front wheels and rear wheels are connected to the pressure increase and pressure relief valves in the hydraulic unit. This arrangement allows each wheel to be controlled independently.

Friction is estimated by calculating the drive wheel torque during acceleration (which is a function of the engine torque) or braking (which is a function of braking force).

If performing evasive action during emergency braking, the vehicle can be maneuvered by regulating the braking pressure applied by the driver using the control module and the pump. The applied braking force on each wheel can therefore be both above and below that requested by the driver.

Braking distance is given priority when braking in a straight line and stability is given priority during evasive action. ESP can be active both when the driver applies the brakes and without the driver even touching the brake pedal.