System and Method for Monitoring Seat Belt Routing Using Both a Webbing Payout Sensor and an In-Cabin Sensor

A system includes a seat belt routing module and a user interface device (UID) control module. The seat belt routing module is configured to: determine a routing of a seat belt relative to an occupant in a vehicle seat based on input from a webbing payout sensor; and determine the seat belt routing based on an input from an in-cabin sensor. The in-cabin sensor includes at least one of a camera, an infrared sensor, an ultrasonic sensor, a radar sensor, and a lidar sensor. The UID control module is configured to control a user interface device to indicate that the seat belt is being worn improperly when: the seat belt routing determined using at least one of the webbing payout sensor and the in-cabin sensor is improper; and the seat belt routing determined using the webbing payout sensor corresponds to the seat belt routing determined using the in-cabin sensor.