Canon PIXMA TR4750i Online Manual page 529

1686
Cause
The ink may have run out.
What to Do
The function for detecting the remaining ink level will be disabled since the ink level cannot be correctly
detected.
If you want to continue printing without this function, press the printer's Stop button for at least 5 seconds.
Canon recommends to use new genuine Canon cartridges in order to obtain optimum qualities.
Please be advised that Canon shall not be liable for any malfunction or trouble caused by using a
non-genuine Canon ink cartridge or by using non-genuine Canon ink.
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