See also:

Brake booster
The brake booster uses engine manifold vacuum to assist braking force. Do not turn off the engine while driving because that will turn off the brake booster, resulting in poor braking power. ...

Vehicle Dynamics Control mode switch (STI)
Indicator light Vehicle Dynamics Control mode switch When the switch is pressed briefly or for more than approximately 3 seconds during engine operation, the mode of the Vehicle Dynamics Control Sys ...

To decrease the speed (by button)
To decrease the speed (by button) Push the “SET/COAST” button and hold it until the vehicle reaches the desired speed. Then, release the button. The vehicle speed at that moment will be m ...