Canon Laser Shot LBP5970 User Manual page 352

By pressing the portion indicated "PUSH", close the top cover firmly until it
cannot be pressed down any further as shown in the figure.
14
By holding the lever as shown in the figure, make sure that
the top cover does not open.
IMPORTANT
Close the top cover firmly until it cannot be pressed down any further. If the top
cover is not closed firmly, this may result in poor print quality.
Replacing Drum Cartridges
6
6-37