HP LaserJet PRO M521 Repair Manua page 8

vi
Right-rear cover ........................................................................................ 30
Tray 1 cover ............................................................................................ 32
Cartridge-door assembly ........................................................................... 34
Right cover assembly ................................................................................ 36
Lower right cover ..................................................................................... 41
Reinstall the lower right cover ..................................................... 43
I/O plate ................................................................................................ 44
Document feeder assemblies and scanner .................................................................. 46
Document feeder/scanner assembly ........................................................... 46
Document feeder whole unit kit and scanner whole unit kit ............................ 52
Document feeder hinge assembly ............................................................... 57
Control-panel top-cover ............................................................................. 57
Control-panel assembly ............................................................................. 59
USB PCA ................................................................................................ 60
Control-panel FFC .................................................................................... 61
USB cable and USB grounding cable ......................................................... 64
Wi-Fi module and cable ............................................................................ 67
Main assemblies ..................................................................................................... 71
Tray 1 pickup roller .................................................................................. 71
Tray 1 separation pad .............................................................................. 73
Tray 2 or Tray 3 pickup roller .................................................................... 74
Tray 2 or Tray 3 separation pad ................................................................ 76
Tray 2 or Tray 3 base-plate roller assembly ................................................. 76
Transfer roller .......................................................................................... 78
Fuser ...................................................................................................... 80
Duplex paper-feed assembly ...................................................................... 83
Registration roller assembly ....................................................................... 86
Power-switch assembly .............................................................................. 88
Interlock-switch assembly ........................................................................... 89
Tray sensor PCA ...................................................................................... 91
Main fan ................................................................................................. 93
Top cover ................................................................................................ 95
Laser scanner ........................................................................................... 98
Tag holder assembly ............................................................................... 101
DC controller ......................................................................................... 102
Low-voltage power supply (LVPS) .............................................................. 106
Tray 2 paper pickup assembly ................................................................. 112
Tray 1 or Tray 2 pickup solenoid ............................................................. 118
Fuser motor ........................................................................................... 120
Pendulum assembly ................................................................................ 121
Sub fan and fan duct .............................................................................. 124
ENWW