Dell 1815dn wont print.

I have a Dell 1815dn. The fuser seems ok but it wont print anything. I have tried 3 brand new cartridges and that is obviously not the problem. It feeds the paper through but fails to print anything on the paper. I have tried printing from the computer,scanner, and right off the menu on the printer. Do you think it is the fuser? I have took it out and it seems fine but it has like an led light bar in it which i havent seen before. Any ideas or suggestions would be great!