Canon printer not scanning problems or printer may not scan -

1.Cables Power and USB are not paired properly.
2.Your drivers are corrupted or obsolete to power the scanner.
3.You don’t clean or break the glass from your Cannon detector.
4.False Scan Parameters are chosen.
5.The code for the scanner is incompatible with the Canon model.
6.Due to infected Windows files, the canon mx490 scanner not working.
7.The multi-use scanner feeder jam problem.

Useful and applicable approaches for addressing scanner problems - 

1.Check the connected cable - Power Cable , USB cable
2.To fix basic problems, clean Scanner Glass
3.Uninstall and Install the newer version of the obsolete IJ Search program
4.Fix or uninstall infected system file

http//ij.start.canonij start canon http // setup