Mix a 50/50 solution of soft water and white vinegar. Use a spray bottle and spray on spots. Take an Absorber cloth and wipe off the spots. Clean again and you can focus on the local of the spots.
Or, get a garage, cover, or put plugs in the sprinkler heads.
Good luck.
Great vinegar advise! That should work to get the spots cleared up, then make sure that you keep it waxed thoroughly! Wax really helps resolve the removal of some idiot sprinkler alignment spots in the future! Most important, if you see this occur in the future, get it washed before it sits in the sun with the hard water spots.... that can be the death of your surface!
I had this calcified sprinkler disaster happen this summer once, and I was fortunate enough to have just waxed it the week prior and that made all the difference getting it back to normal. A new discovery on black plastic with signs of water spots or hard water dulling, is to use the Turtle Wax Ice product. It is great on the bare plastic, won't leave any residue like regular wax, and really cleans up the surface. Used it on the side mirrors and now the bugs won't stick to them!
Sorry this happened to you man, you'll get it cleaned up, then park far away from any possible sprinkler area!
