Black spot hell on White paint

[chinee]

My white car (medium sized SUV - Toyota Rav4) was progressively getting covered in black spots. I've read through lots of blogs and there doesn't seem to be a consensus. However, I decided to try the easiest... I used white vinegar and warm water with a ratio of approx. 1:10. It worked a treat. It took a good couple of hours to wipe down the whole car. I think I will need to go over it again, especially in the corners and joins, but it looks 100% better already.

Here is the difference around the top of the door frame...
Attachment 67395

Here is it on the door panel...
Attachment 67396

What is your car care regimen? I ask because it looks like mold and mildew on paint (on the road film on the paint) that's not regularly washed.

[Aussie Rowan]

Hi. Having read this blog, I'm pretty sure it was artillery mould / fungus. It was almost impossible to remove until I used the diluted white vinegar which got rid of it relatively easily. And you are right, I need to wash the car more regularly!