4 Theory of operation Basic operation ................................................................................................................................... 30 Modes and control-panel indicators ................................................................................................... 31 Circuit board assemblies .................................................................................................................... 32 Fans ...................................................................................................................................................
33 ADF feed system ................................................................................................................................ 34 Sensors .............................................................................................................................. 34 Motors ................................................................................................................................ 35 Service block diagram ........................................................................................................................
36 5 Removal and replacement Removal and replacement strategy .................................................................................................... 38 General cautions during removal and replacement ........................................................... 38 Electrostatic discharge ....................................................................................................... 38 Required tools .................................................................................................................... 39 Cleaning supplies ..............................................................................................................
39 Screws and fasteners ........................................................................................................ 39 Before performing service .................................................................................................. 39 After performing service ..................................................................................................... 40 User-replaceable parts ....................................................................................................................... 41 Imprinter cartridge ..............................................................................................................
42 Fan filters ........................................................................................................................... 44 ADF base reflector ............................................................................................................. 45 Reinstall the ADF base reflector ....................................................................... 46 Pickup-roller assembly ....................................................................................................... 47 Reinstall the pickup-roller assembly ..................................................................
48 Separation-pad assembly .................................................................................................. 49 Reinstall the separation-pad assembly ............................................................. 50 External covers ................................................................................................................................... 51 Scanner control-panel cover .............................................................................................. 52 Scanner back-filter cover ...................................................................................................
53 Scanner right-filter cover .................................................................................................... 53 ADF front cover .................................................................................................................. 54 ADF back cover ................................................................................................................. 57 Scanner back cover ........................................................................................................... 59 Automatic document feeder FRUs .....................................................................................................
60 Automatic document feeder (ADF) .................................................................................... 62 Reinstall the ADF .............................................................................................. 66 ADF height adjustment ...................................................................................... 70 NVRAM data management ............................................................................... 73 Repair menu ..................................................................................... 73 Repair menu options ........................................................................
74 Replacement scenarios .................................................................... 75 iv ENWW