HP LaserJet Pro 400 MFP M425 Service Manual and Parts List Manual

This Service Manual contain: Repair Manual and Troubleshooting Manual HP LaserJet Pro 400 MFP M425.
Accurate, clear and concise text, combined with detailed illustrations, lists of error code, instruction and diagrams, guide you through procedure of repair, remediate, maintenance and adjustments your copier, printer or scanner.
Present service manual HP LaserJet Pro 400 MFP M425 contain clear instructions and procedures on how to fix the problems occurring in your equipment.
The information contained in this repair manual is necessary for the repair, but also prevention, resulting in a longer life of your equipment.
Format of the manual: PDF, makes it easy to navigate, instant download and print. English language.
To see what contain, please read table of contents:

Content for REPAIR & PARTS LIST:
Removal and replacement strategy
Electrostatic discharge
Required tools
Types of screws
Service approach
Before performing service
After performing service
Post-service test
Print-quality test
Parts removal order
Removal and replacement procedures
Multipurpose (MP) tray pickup roller
Multipurpose (MP) tray separation pad
Tray 2 and optional Tray 3 pickup roller
Tray 2 and optional Tray 3 separation pad
Document feeder rollers
Document feeder separation pad
Covers, scanner assembly, and control panel
Left cover
Scanner assembly
Control panel
Right cover
Top cover
Rear cover, rear door, and feed assembly
Cartridge door and front cover assembly
Main assemblies
Laser scanner assembly
Registration assembly
Fuser assembly and paper feed guide
Duplex drive assembly
Tray 1 solenoid
Duplex solenoid
Motors and fans
Main motor
Printed circuit-board assemblies (PCAs)
Engine controller assembly (DC controller) PCA
Universal serial bus (USB) PCA
Formatter PCA
Wireless PCA
Power switch PCA
Connecting PCA
Miscellaneous parts
Transfer roller
Multipurpose (MP) tray pickup gear assembly
Document feeder assembly
Optional paper feeder (Tray 3)
Optional paper feeder right cover
Optional paper feeder driver PCA
Optional paper feeder paper sensor PCA

Order parts by authorized service providers
Order replacement parts
Related documentation and software
Supplies part numbers
Whole-unit replacement part numbers
How to use the parts lists and diagrams
Assembly locations
Main unit
Optional paper feeder
Covers, panels, and doors
Internal assemblies
Scanner and document feeder
Input devices
500-sheet paper feeder
Paper feeder covers
Paper feeder main body (1 of 2)
Paper feeder main body (2 of 2)
Alphabetical parts list
Numerical parts list


Basic operation
Major product systems
Product components
Sequence of operation
Engine control system
DC controller
Motor control
Fan control
High-voltage power supply
Fuser control circuit
Fuser temperature control
Fuser protection function
Fuser failure detection
Low-voltage power supply
Protective function
Low-voltage power supply unit failure detection
Laser scanner system
Laser failure detection
Image-formation system
Image-formation process
Latent-image formation stage
Step 1: Primary charging
Step 2: Laser-beam exposure
Developing stage
Step 3: Development
Transfer stage
Step 4: Transfer
Step 5: Separation
Fusing stage
Step 6: Fusing
Drum cleaning stage
Step 7: Drum cleaning
Pickup and feed system
Jam detection
Paper feeder (optional Tray 3)
Paper feeder operation
Jam detection
Scanner system
Scanner power-on sequence of events
Copy or scan sequence of events
Fax functions and operation
Computer and network security features
PSTN operation
Receive faxes when you hear fax tones
Distinctive ring function
Use fax with voice over IP services
The fax subsystem
Fax card in the fax subsystem
Safety isolation
Safety-protection circuitry
Data path
Hook state
Downstream device detection
Hook switch control
Ring detect
Line current control
Billing- (metering-) tone filters
Fax page