Abstract: At least one sensor mounted to an open vehicle such as a convertible can be connected into a circuit with a power source and a motorized roof portion. The sensor is able to determine the presence of conditions such as clouds, rain, or night, by recording and measuring a stimulus. If the measured stimulus crosses a predetermined threshold, a switch closes in order to complete the circuit. The completed circuit thus supplies power to the motorized roof portion, resulting in the motorized roof portion closing without direct human manipulation. In addition to the motorized roof portion, a motorized window and a power lock can be electrically connected into the circuit. As a result, not only can the motorized roof portion be automatically closed, the motorized window can automatically be closed and the power lock can be automatically locked.