Is probably a silly question…….But I really don't know. Thanks.

 

Basically, it is a radar system that monitors your blind spots. Also, when backing out of a parking space, or driveway, it lets you know of things you may not be able to see. It is a must have, in my opinion, on these big trucks. It has saved my rear end a few times.

Here is a video of how it works on a smaller car, but the principle is the same.

 

Blind spot information system, it uses radar in the tail lamps to tell you, with an orange light in the mirror, if there's a car or something in your blind spot. On the super duty and apparently F-150 now, that includes trailer coverage, which means if you have a conventional or bumper pull trailer that's total length hitch coupler to end of trailer less than I think 33 feet, you can set it up in your towing menu and it'll extend that radar to your trailer so it'll tell you if there's something in your trailers blind spot now, it's pretty cool