Secure method for control of a function by means of a touchpad

A method for the secure control of an apparatus by way of a system, wherein the method comprises at least the following steps:

• displaying a first symbol corresponding to a first initial state of the apparatus;
• displaying a second symbol corresponding to a second state of the apparatus;
• implementing the second state of the apparatus by way of a single continuous press on a touch surface starting on the first symbol, passing through a first crossing point situated at the first symbol, following a pattern comprising a part passing diagonally through a plurality of rows and columns of a matrix, passing through a second crossing point situated at the second symbol and finishing on the second symbol;
• wherein the system comprises a viewing device comprising the touch surface formed of the matrix of conductive rows and columns, a viewing screen and a processing and control unit for said apparatus, said processing unit comprising a first assembly for processing positioning information coming from the touch surface and a second assembly for displaying graphical symbols on the viewing device, and
• wherein the second symbol is displayed only when the first symbol is called upon by being touched.