Epson Stylus Color 660 Manual page 46

Do not use the Nozzle Check, Head Cleaning, and Print Head
Alignment utilities with printers connected to your computer
through a network.
Do not use the Nozzle Check, Head Cleaning, and Print Head
Alignment utilities while printing is in progress; otherwise, your
printout may be marred.
Status Monitor 3
Provides you with printer status information, such as the amount
of ink remaining, and checks for printer errors.
This utility is available only when:
The printer is connected directly to the host computer via the
parallel port [LPT1], and
Your system is configured to support bidirectional
communication.
Nozzle Check
Checks the print head nozzles for clogging. Check the nozzles if
you notice print quality has declined and after cleaning to confirm
that the print head nozzles have been cleared. If the nozzle check
indicates the print head needs cleaning, you can access the Head
Cleaning utility directly from the Nozzle Check utility. See
"Checking the Print Head Nozzles".
Head Cleaning
Cleans the print head. You may need to clean the head when you
notice print quality has declined. Use the Nozzle Check utility
first to confirm that the head needs to be cleaned. You can access
the Nozzle Check utility directly from the Head Cleaning utility.
See "Cleaning the Print Head".
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