2008 F450/F550 Tail light wires from harness

I have 2008 f550 and I am not sure which wires do what coming out of the rear tailight harness I hook everything up and then the left turn signal at the back dose not work but the front one works ????

Can anyone help me with which colors do what on the harness
And if this is a problem as I read that on 2008 the flashers are controlled by a computer if the front works is there a seperate circut in that computer has for the rear one?

Any ideas would help ??

Thanks:no: