Canon pro-10s series Online Manual page 444

1698
Cause
Printer detected ink out condition (The lamp on the ink tank flashes).
Action
If printing is in progress, stop printing, replace the ink tank, and then print again.
To avoid printing troubles such as the mixing of inks, this printer is designed to stop printing by flashing
the Alarm lamp seventeen times when the remaining ink level in an ink tank goes under the amount of ink
required to maintain both printer and print quality.
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