Canon PIXMA iP5300 Service Manual page 49

Empty: No raw ink is detected by the optical method, and the dot count value
exceeds the threshold of complete exhaustion of ink.
A warning will be displayed to indicate that ink has run out.
By pressing and holding the Resume/Cancel button for 5 seconds or longer,
the function to detect the remaining ink amount can be disabled.
Unknown: Raw ink remains, but the dot count value exceeds the threshold of complete
exhaustion of ink.
By pressing and holding the Resume/Cancel button for 5 seconds or longer,
the function to detect the remaining ink amount can be disabled.
The remaining ink amount will be checked at any of the following timings:
- At the end of paper ejection
- At the end of print head cleaning
- At the end of initialization
- At the end of the following operation:
Cover open => Ink tank removal and installation => Cover close
- In duplex printing, at the end of paper ejection after printing on the back side of paper
*1: Not every paper ejection. Only after the dot count exceeds the specified value.
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