What happens to scars in the sun, will they be ugly if they get tanned?

I have along scar on my upper arm, I broke it in a car crash over 3 years ago. I usually have a scarf with me and wear this over it to avoid it getting ugly. I've heard this is what happens to scars if they get tanned. As its quite big and kinda in your face if I wear short sleeves I would like it to stay someway nice. I have no problem with having it. I kinda like it so don't need to hide it but just afraid of it going ugly is this what would happen if it got too much sun or would it be ok. It's a very tidy scar and has faded somewhat to a pale red pinkish colour. Should I just keep it covered when in the sun.