An orientation-based wireless sensor includes a transmitter unit having a body housing a microprocessor, a transmitter, and an accelerometer for detecting the orientation of the transmitter unit relative to one-, two- or three-axis of the direction of the pull of earth's gravity. The transmitter body is mounted on a feature of a vehicle that it is desirable to monitor. The transmitter will transmit orientation data at predetermined time intervals to a receiver on the vehicle, which will in turn process the information, adding additional information, such as GPS location, and wirelessly send the data to a database that is available to a customer over the Internet.