Epson EPL-6100 Reference Manual page 226

There may be a problem with
the developer cartridge.
The image is too dark
Cause
There may be a problem with
the developer cartridge.
Non-printed side of the page is dirty
Cause
Toner may have spilled onto
the paper feed path.
Warning:
w
Be careful not to touch the fuser, which is marked CAUTION
HOT Surface Avoid Contact, or the surrounding areas. If the
printer has been in use, the fuser and the surrounding areas may
be very hot.
124 Troubleshooting
Take out the developer cartridge, shake
it gently from side to side to distribute
the toner, and then reinstall it. If the
problem persists, replace the cartridge
as described under "Replacing the
Developer Cartridge" on page 73.
What to do
If the problem persists, replace the
developer cartridge as described under
"Replacing the Developer Cartridge" on
page 73.
What to do
Turn off the printer. Clean internal
printer components.