Lexmark C720 User Reference Manual page 172

What you can do:
Correctly install the fuser to clear the message and continue printing.
See also:
Fuser and air filter
88 <color>
Toner Empty
What this message means:
The printer has ceased operating because the specified toner cartridge is empty. You cannot
print until you replace the specified toner cartridge.
What you can do:
Install a new toner cartridge.
See also:
Toner cartridges
88 <color> Toner
Low
What this message means:
The printer has detected that the toner supply in the specified cartridge is low. If you do not
have the specified toner cartridge on hand, order one now. You can print approximately 250
pages before the 88 <color> Toner Empty message appears and the printer ceases
operating.
What you can do:
•
Replace the specified toner cartridge.
•
Press to clear the message and continue printing. The Supplies message is displayed on
Go
the second line of the operator panel until you replace the specified toner cartridge.
See also:
Toner cartridges
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