See also:

Horn
Audible warning system to alert other road users to an imminent danger. Press the central part of the multifunction steering wheel. Use the horn moderately and only in the following circumstances: ...

Brake disc wear
For information on checking brake disc wear, contact a PEUGEOT dealer or a qualified workshop. ...

Emergency braking
In the event of a failure of the main service brake or in an exceptional situation (e.g. driver taken ill, under instruction, etc) a continuous pull on the control lever A will stop the vehicle ...