A warning system that includes a first sensor configured to measure a first signal representative of the state of a door, at least one trim element having at least one second sensor configured to measure a second signal representative of a force applied to the trim element. The system also includes a warning computer and a warning device to communicate warning data to a user. The computer includes: an acquisition module configured to acquire the first signal and the second signal, a determination module configured to determine the warning data based on the first and second signals. The determination module is configured to determine the warning data if the first signal is representative of an open state of the door and if the second signal is representative of an applied force greater than a threshold force.