One problem related to blind spot detection has been reported for the 2016 Ford Flex. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2016 Ford Flex based on all problems reported for the 2016 Flex.
Camera recall number is 25s72 (NHTSA 25v442000). I own a 2016 Ford Flex and its having the same issue. I had the camera replaced at the dealership out of pocket once before and its still not working. I feel my issue is the same as this recall just affecting a different model.