The stiction phenomenon which results in the adhesion of the brake pad to the disc brake of a vehicle has been investigated from a corrosion point of view. Asbestos-free organic pad that contains copper associated with a cast iron disc was investigated and compared to a model system which consisted in a ceramic pad (chemically inert) associated with the same cast iron disc. The whole system was described as a thin-layer cell of electrolyte and was studied using different electrochemical methods including polarization curves and impedance spectroscopy. The influence of the cell geometry was pointed out, but the corrosion of the system is enhanced due to the presence of copper in the pad. Indeed, the copper dissolves from the pad and redeposits on the disc. This was confirmed by scanning electron microscopy observations and Raman spectroscopy. A mechanism taking into account the thin-layer geometry was then proposed to account for the role of metallic additive (in this case copper) on the corrosion of the disc.