HP Laser Jet 5550 - Page 9

6 Removal and replacement
Introduction ............................................................................................................................185
Removal and replacement strategy ................................................................................185
Repair notices .................................................................................................................185
Caution regarding electrostatic discharge (ESD) ...........................................................185
Required tools .................................................................................................................185
Types of screws ..............................................................................................................186
Supplies .................................................................................................................................188
Print cartridges and ETB ................................................................................................189
Covers and external components .........................................................................................190
Rear cover ......................................................................................................................190
Top cover ........................................................................................................................190
Rear top cover ................................................................................................................191
Left cover ........................................................................................................................192
Right cover ......................................................................................................................193
Reinstallation tip .............................................................................................................194
Multi-purpose tray (Tray 1) .............................................................................................194
Front cover ......................................................................................................................195
Control panel ..................................................................................................................196
Cassette cover ................................................................................................................198
Internal components (front) ...................................................................................................199
Paper pickup unit ............................................................................................................199
Cassette sensor PCB .....................................................................................................200
Multi-purpose tray sensor PCB ......................................................................................200
Paper pickup drive unit .................................................................................................201
Lifter drive unit ..............................................................................................................202
Cassette (Tray 2) paper pickup and feed rollers ............................................................204
Solenoid and clutch ........................................................................................................205
Cassette separation roller .............................................................................................206
Multi-purpose tray pickup roller ......................................................................................207
Multi-purpose tray separation pad .................................................................................208
Color registration detection unit ......................................................................................208
Internal components (left side) ..............................................................................................210
DC controller shield ........................................................................................................210
Environment sensor (HP Color LaserJet 5550 models) .................................................210
Memory tag antenna PCBs ............................................................................................211
E-label memory controller PCB ......................................................................................217
DC controller PCB ..........................................................................................................218
Cassette paper size detection switches .........................................................................219
Power supply fan ............................................................................................................220
Internal components (rear) ....................................................................................................222
Formatter ........................................................................................................................222
Low-voltage power supply ..............................................................................................223
Formatter case ................................................................................................................225
Laser/scanner units ........................................................................................................227
Internal components (right side) ...........................................................................................233
High-voltage power supply PCB .....................................................................................233
Toner level detection PCB ..............................................................................................234
High-voltage contact blocks ............................................................................................235
Door switch .....................................................................................................................236
Internal components (top) .....................................................................................................238
Discharging PCB ............................................................................................................238
Fuser power supply PCB ................................................................................................239
Fuser drive unit ...............................................................................................................240
Fuser inlet paper sensor .................................................................................................243
Fuser delivery sensor and output bin full sensor ............................................................244
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