Removal and replacement strategy
.....................................................................................................
168
Required tools
.....................................................................................................................
168
Before performing service
..................................................................................................
169
After completing service
....................................................................................................
169
Screws used in the printer
.................................................................................................
170
Parts-removal tree
.............................................................................................................
171
Printer input tray, and cabinet wheel locks
.........................................................................
172
Dc controller PCA diagram
.................................................................................................
173
User-replaceable parts
......................................................................................................................
175
Print cartridge
.....................................................................................................................
175
Transfer roller
....................................................................................................................
177
Fuser
...................................................................................................................................
178
Tray 1 pickup roller
............................................................................................................
179
Tray 1 separation pad
.........................................................................................................
181
Tray 2 feed rollers
...............................................................................................................
182
Covers, tray 1, and the rear output bin
................................................................................................
186
Accessory covers and the tray 2 extension door
...............................................................
187
Formatter cover
...................................................................................................................
191
Top cover
............................................................................................................................
192
Right-side cover
.................................................................................................................
195
Left-side cover
....................................................................................................................
197
Front cover
..........................................................................................................................
198
Tray 1
..................................................................................................................................
200
Rear output bin
...................................................................................................................
203
Control-panel display
...........................................................................................................................
204
Control-panel overlay
.........................................................................................................
204
Control-panel assembly
.....................................................................................................
205
Main assemblies
.................................................................................................................................
209
Firmware DIMM (LJ 4200/4300 only)
.................................................................................
210
Formatter assembly
...........................................................................................................
211
Reinstallation notes, formatter
...........................................................................................
212
Installing a new formatter and a new dc controller (LJ 4250/4350 only)
............................
213
Output-delivery assembly
..................................................................................................
214
Duplexing-pendulum assembly
...........................................................................................
217
Laser/scanner assembly
.....................................................................................................
219
Paper-pickup drive assembly
.............................................................................................
222
Tray 2 lifter-drive assembly
.................................................................................................
227
Dc controller PCA
...............................................................................................................
230
Reinstallation tip
..................................................................................................................
235
Installing a new formatter and a new dc controller (LJ 4250/4350 only)
............................
235
Power supply
......................................................................................................................
236
Paper-feed belt assembly
...................................................................................................
243
Motors and fans
...................................................................................................................................
245
Main cooling fan (left side)
.................................................................................................
246
Cooling fan, right side (HP LaserJet 4250/4300/4350 Series printers only)
.....................
248
Removing the fan without removing the air duct
................................................
248
Removing the fan and the air duct together
.......................................................
251
Print-cartridge motor (HP LaserJet 4250/4300/4350 series printer only)
...........................
253
Main motor
.........................................................................................................................
255
Pickup and feed assemblies
...............................................................................................................
257
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