Apple COLOR STYLEWRITER 2400 - Manual (Page 22)

Checking the print nozzles
The Color StyleWriter 2400 prints by spraying colored ink onto the paper
through tiny nozzles. Sometimes these small nozzles can get clogged after
sitting unused for a long time. To make sure all the nozzles are working,
follow these steps.
1 If necessary, turn off the printer.
The green power light should be off.
2 Press and hold down the power button until the power light starts to blink.
3 Release the button and wait for the test page to print.
Press the power button.
When the power light
blinks, release the button.
15 Setting Up Your Printer