Full gray back ground MX-M503N

[Jaws]

I saw a post on a MX-M363 with back ground issues but I don't think it is the same problem. I am getting a full gray back ground on prints, copies also. I swapped developer units, I swapped drum units, and I swapped transfer units, still having the same issue with this machine and it did not phase the others , they are still working fine. See my picture, scratch your head, and write down your best guess. Machine worked perfect until we moved it on site. I am thinking a back solder joint.
MX-M503N Pritn Problem.jpg

[ZOOTECH]

I saw a post on a MX-M363 with back ground issues but I don't think it is the same problem. I am getting a full gray back ground on prints, copies also. I swapped developer units, I swapped drum units, and I swapped transfer units, still having the same issue with this machine and it did not phase the others , they are still working fine. See my picture, scratch your head, and write down your best guess. Machine worked perfect until we moved it on site. I am thinking a back solder joint.
MX-M503N Pritn Problem.jpg

Check, and reseat LSU connectors.