Cause
The 1688 support code signifies that the printer has detected that one or more of your ink cartridges is empty.
What to Do
The action you should take to resume operating the printer depends upon which function(s) of the printer you intend to use.
1. To PRINT or COPY
If you intend to PRINT or COPY, you should take one of the following steps:
(a) Disable the function that detects the level of ink remaining by pressing the Stop 
button on the printer for at least five (5) seconds and then releasing it.
If, due to individual usage factors, there is some residual amount of ink in the cartridge(s), you will be able to PRINT or COPY until the remaining ink is depleted.
Please note that image quality may be diminished if you PRINT or COPY when there is little ink remaining in the cartridge(s).
OR
(b) Open the scanning unit / cover, replace each ink cartridge identified by the printer as being empty, and close the scanning unit / cover.
Canon recommends the use of new, genuine Canon ink cartridges for optimal image quality.
2. To SCAN
If you intend to SCAN, you should take one of the following steps:
(a) Disable the function that detects the level of ink remaining by pressing the Stop button on the printer for at least five (5) seconds and then releasing it.
OR
(b) Open the scanning unit / cover, replace each ink cartridge identified by the printer as being empty, and close the scanning unit / cover.
Canon recommends the use of new, genuine Canon ink cartridges for optimal image quality.
If the function for detecting the level of ink remaining in an ink cartridge is disabled, the ink cartridge will be displayed in white on the touch screen (if the printer has a touch screen) when you check the estimated remaining ink level.
If your product issue was not resolved after following the steps above, or if you require additional help, please create or log in to your Canon Account to see your technical support options.
Or if you still need help, visit our Canon Community by clicking the button below to get answers:
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