Epson AcuLaser C3000 Series User Manual page 264

Sleep
The printer is in sleep mode.
In this mode, the remaining amount of the toner cartridge for each
color is displayed in seven levels.
TonerCart Error xxxx
A read/write error has occurred for the indicated toner cartridges
(The letters C, M, Y, or K appear in place of XXXX and indicate
the colors Cyan, Magenta, Yellow, and Black respectively.).
Replace the toner cartridges. If that fails to clear the error, turn the
printer off.
Install the indicated cartridges. See "Toner Cartridge" on page
181.
Unable Clear Error
The printer cannot clear an error message because the error status
still remains. Try solving the problem again.
Worn Fuser
This message indicates that the fuser unit has reached the end of
its service life. Printing after this message appears is not
guaranteed. Turn the printer off, and reinstall the unit after it has
cooled off (30 minutes). Then replace the fuser unit with a new
one. See "Fuser Unit" on page 193 for instructions.
The error clears automatically after you replace the unit and close
all printer covers.
264
Troubleshooting