Canon Color imageCLASS MF8170c Basic Manual page 130

IMPORTANT
Lock the drum cartridge securely so that it may be in the state shown in the figure.
Close the cartridge cover and lower the scanning platform.
9
If the message is still displayed after closing the cartridge cover, pieces of torn paper
may still be remaining inside. Re-check the various sections of the machine and
remove all pieces of the jammed paper from inside the machine.
9-8 Clearing Jams