When it involves the latest features in today's vehicles (ADAS -Advanced Driver Assistance Systems) there is not too much you can do to help yourself. Special equipment ( Capable scan tool) is usually required to determine the cause and most folks don't have that equipment nor know what to do with it.
What you can do is , check all the fuses first. If you have the correct rating fuse , just replace a blown fuse and see what you get. Sometimes, a momentary glitch will cause a fuse to open and replacing it can get things working again. Other than that , it will require some detailed testing to isolate and determine exactly what is causing the problem.
Some have ultrasonic sensors mounted in the fenders coupled with sensors mounted in the windshield that tied together with the power steering , vehicle stability system,and anti lock brake system all work together to help keep the vehicle in it's intended path. This kinda gets most of us out of the diagnosis and repair picture.
Something as simple as cleaning the windshield can help if that is the area not able to do it's job.