The back up camera in my 2011 F150 Lariat would only show blue screen at times and other times would work fine. The camera is in the review mirror. About the same time I could not get the settings for VISUAL PARK AID to stay on and the GUIDELINES to stay on fixed. What am I missing. That all used to work fine. The last time the camera worked I went immediately into settings and set VISUAL PARK AID to on, and GUIDELINES to fixed but they would immediately go to off. Even while the camera showed an image.

Where do I start?
Thanks
David W