To confirm: The California vehicle code does prohibit windshield mounted electronic devices.
However, unlike the new California "hands free" cellphone mandate, which is a primary violation that permits a law enforcement officer to stop a motorist for violation of that statute alone, the "nothing attached to the windshield" statute is not necessarily probable cause for a traffic stop when the officer does not observe any other violation.
That being said, anyone driving a modified offroad vehicle is most likely probable cause on wheels as it is difficult to install auxilliary lights, larger tires, winch, etc. without violating some California equipment regulation. (i.e., are your auxilliary lights lower than the height that requires a cover or have bulbs with wattage greater than the statutory limit, do your tires extend beyond the fender flares, or do you still have your front license plate after installing your winch?)
It all comes down to the unwritten "attitude test." Don't drive like a jerk or otherwise draw unwanted attention to yourself. If you are pulled over, avoid furtive gestures, keep both hands on the wheel, ask for permission to reach for your license and registration, say "no" (and nothing else) when asked if you know what you did wrong, remain calm and polite, and act confused and apologetic when the officer tells you (while admitting nothing). You may well get a warning, instructions to "get that damn thing off your windshield" (or "cover those lights," "put your front plate on," etc.), and be sent on your way.
I can't tell you how many times that scenario has played out for me. :smiley_drive:
