Canon Pro-1000 series Online Manual page 760

1753
Cause
The remaining level of the ink cannot be correctly detected.
What to Do
Replace the ink tank. Printing will restart.
Replacing Ink
An ink tank that was once empty is installed.
If you want to continue printing, you need to disable the function for detecting the remaining ink level.
To disable this function, press and hold the printer's Stop button for at least 5 seconds, and then release
it.
With this operation, disabling the function for detecting the remaining ink level is memorized.
Please be advised that Canon shall not be liable for any malfunction or trouble caused by continuation of
printing under the ink out condition or by using refilled ink tanks.
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