Contents2.7.2 Protection Function ........................................................................................... 2-38Chapter 3 Parts Replacement Procedure3.1 External Covers.......................................................................................................... 3-13.1.1 Rear Upper Cover ...............................................................................................3-13.1.2 Grate-shaped Upper Guide ..................................................................................3-13.1.3 Grate-shaped Lower Guide .................................................................................3-13.1.4 Front Inside Upper Cover ....................................................................................3-23.1.5 Front Door ...........................................................................................................3-33.1.6 Escape Tray Cover ..............................................................................................3-43.1.7 Escape Door ........................................................................................................3-43.2 Drive System.............................................................................................................. 3-53.2.1 Stapler .................................................................................................................3-53.2.2 Swing Unit ..........................................................................................................3-63.3 Document Feeding System ........................................................................................ 3-93.3.1 Process Tray Assembly .......................................................................................3-93.3.2 Tray 1 ................................................................................................................3-113.3.3 Tray 2 ................................................................................................................3-133.3.4 Buffer Roller .....................................................................................................3-153.3.5 Return Roller .....................................................................................................3-163.3.6 Return Roller Unit .............................................................................................3-173.3.7 Escape Unit .......................................................................................................3-183.3.8 Escape Door Unit ..............................................................................................3-203.4 Electrical System ..................................................................................................... 3-213.4.1 Finisher Controller PCB ....................................................................................3-213.4.2 Static Charge Eliminator 1 ................................................................................3-223.4.3 Static Charge Eliminator 2 ................................................................................3-233.4.4 Static Charge Eliminator 3 ................................................................................3-24Chapter 4 Maintenance4.1 User Maintenance ...................................................................................................... 4-14.1.1 User Maintenance (Finisher Unit)....................................................................... 4-14.2 Maintenance and Inspection ...................................................................................... 4-24.2.1 Periodically Replaced Parts .................................................................................4-24.2.1.1 Periodically Replaced Parts (Finisher Unit)................................................. 4-24.2.2 Durables ..............................................................................................................4-24.2.2.1 Durables (Finisher Unit)............................................................................... 4-2