Canon i-SENSYS MF3010 User Manual page 159

See the following section and check the display contents and the actions.
"Operation Panel and Display"
Do an "E" and a subsequent three-digit number repeatedly appear on the display?
Some sort of error has occurred in the printer.
Turn OFF the power switch, wait at least 10 seconds, and then turn it ON again. If the problem is not solved, write down
the three-digit number that is displayed, turn OFF the main power switch, disconnect the power cord, and contact the
Canon help line.
If you continue to experience problems after trying the actions suggested in this section, see the following sections to solve
the problems.
"Paper Feeding Problems"
"Copying Problems"
"Printing Problems"
"Scanning Problems"
"Installation and Uninstallation Problems"
"Miscellaneous Problems"