Canon imagePRESS C850 Series Troubleshooting Manual page 35

2-3) Shift the tray cable cover [1] toward the tray side to remove.
2-4) In the case of the Booklet Finisher, remove six screws [2] and remove the rear cover [3]. In the case of the Staple Finisher,
remove five screws [2] and remove the rear cover [3].
2-5) Remove four screws [1] and then remove the front inside upper cover [2]. (This step is unnecessary for the staple finisher.)
33