Canon PRO-100S series Online Manual page 559

1683
Cause
The remaining ink level cannot be correctly detected. (The lamp on the ink tank flashes.)
Action
Replace the ink tank and close the top cover.
Printing with an ink tank that was once empty may damage the printer.
If you want to continue printing in this condition, you need to release the function for detecting the
remaining ink level. Press and hold the printer's RESUME/CANCEL button for at least 5 seconds, and
then release it.
With this operation, releasing the function for detecting the remaining ink level is memorized. Please be
advised that Canon shall not be liable for any printer malfunction or damage caused by refilled ink tanks.
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