cited for improper u-turn but sign was blocked

[outsiderr]

What is the name of your state? Georgia

The other day I was ticketed for making an improper u-turn but the sign that says that the u-turn was not allowed was blocked from my view. When I was making the u-turn, a construction crew with a truck was in front of the sign. After I made the u-turn, within about a couple of hundred feet, I was pulled over. At first I thought the cop had pulled me over for making a u-turn at a "construction site" and there might be some law against that, but he said that I was allowed to make a u-turn even if there are construction workers at the intersection. He then told the reason why I was pulled over was because there is a sign that says no u-turn. I tried to to tell him that I was unable to see the sign and it was blocked from my view. If I plead against this in court, do I have a chance of winning? Is it fair to ticket someone for violating a sign when they cannot even see the sign?