A capacitive measurement device includes: at least one measurement electrode having an active surface; at least one guard made from an electrically conductive material placed adjacent to the measurement electrode(s), the guard being excited up to an alternating electric potential substantially identical to that of the measurement electrodes; and a first electronic device for exciting the electrode(s) and processing the measurement signals from the capacitive coupling of the electrode(s) to an object placed adjacent thereto, the electronic device being at least partially referenced to the electric potential of the guard. The measurement device further includes apparatus for performing another function, placed adjacent to the active surface, and a second electronic device provided for monitoring the apparatus for performing another function, the second electronic device being at least partially referenced to the electric potential of the guard.