HP LaserJet Pro M125MFP M126MFP M127MFP M128MFP Service Manual and Parts Catalog

This Service Manual contain: Repair Manual and Troubleshooting Manual HP LaserJet Pro M125MFP M126MFP M127MFP M128MFP.
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 contain clear instructions and procedures on how to fix the problems occurring in your equipment.
Format of the manual: PDF, makes it easy to navigate, instant download and print. English language.
Table of contents:

Content for REPAIR MANUAL:
1) Removal and replacement
Removal and replacement strategy
Required tools
Types of screws
Service approach
Before performing service
After performing service
Parts removal order
Removal and replacement procedures
Customer-replaceable parts
Toner cartridge
Input tray
Short-media extender
Pickup roller
Separation pad
Handset (M128fp model only)
Covers and external components
Paper-delivery tray (output bin extension)
Left cover
Remove the left cover
Scanner assembly
Remove the scanner assembly
Cartridge door
Remove the cartridge door
Front cover and control-panel assembly
Remove the front cover
Remove the control-panel assembly
Right cover
Remove the right cover
Top cover and image scanner lock
Remove the top cover and image scanner lock
Rear cover
Remove the rear cover
Reinstall the rear cover
Main assemblies
Transfer roller
Left-side PCAs
Wireless PCA (wireless models only)
Formatter PCA
Fax PCA (fax models only)
Laser scanner assembly and cable
Remove the laser scanner assembly and cable
Motor PCA and motor
Remove the motor PCA and motor
Engine controller PCA
Remove the engine controller PCA
Reinstall the engine controller PCA
Fuser and delivery sensor PCA
Remove the fuser and delivery sensor PCA
Reinstall the fuser
Pickup assembly and pickup sensor PCA
Remove the pickup assembly and pickup sensor PCA
Reinstall tips for the grounding spring and lifting plate
Scanner and document feeder components
Separate the scanner lid or document feeder from the scan base
Scanner components
Scan bezel
Scan drive system
Scan FFC cable
Scan motor
Scanner spring assembly
Document feeder components
Document feeder (ADF) top cover
ADF core
ADF separation pad
ADF inner tray
ADF input guides and gear
ADF pre-pickup arm assembly

2) Parts and diagrams
Order parts by authorized service providers
Order replacement parts
Related documentation
Supplies part numbers
Customer replaceable units (CRU) kit part numbers
Whole-unit replacement part numbers
How to use the parts lists and diagrams
Covers and external components
Internal assemblies
Internal assemblies (1 of 3)
Internal assemblies (2 of 3)
Internal assemblies (3 of 3)
Scanner and document feeder components
Scanner lid, base models
Scanner assembly, base models
Scan drive system, all models
Scanner and document feeder assembly, fax models
Scanner assembly, fax models
Document feeder assembly, fax models
Document feeder top cover, fax models
Document feeder core, fax models
Alphabetical parts list
Numerical parts list

1) Theory of operation
Basic operation
Major product systems
Product block diagram
Sequence of operation
Normal sequence of operation
Formatter-control system
Sleep mode
PJL overview
LEDM overview
ACL overview
Control panel
Engine-control system
Motors, solenoids, switches, and sensors
DC controller operations
Fuser-control circuit
Fuser failure detection
Fuser temperature control
Fuser protective function
Pressure roller cleaning
Low-voltage power supply
Over-current/over-voltage protection
High-voltage power supply
Laser/scanner system
Laser failure detection
Image-formation system
Electrophotographic process
Image formation process
Latent-image formation stage
Primary charging
Laser beam exposure
Developing stage
Toner cartridge
Transfer stage
Fusing stage
Cleaning stage
Pickup, feed, and delivery system
Photo sensors, motor, and solenoid
Jam detection
Scanner system
Electrical system
Scanner power-on sequence of events
Copy or scan-to-computer sequence of events
Document feeder functions and operation
Document feeder operation
Document feeder paper path and document feeder sensors
Document feeder jam detection
Fax functions and operation
Computer and network security features
PSTN operation
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 storage in flash memory
Stored fax pages
Advantages of flash memory storage

2) Solve problems
Solve problems checklist
Troubleshooting process
Determine the problem source
Power subsystem
Power-on checks
Tools for troubleshooting
Component diagnostics
Engine diagnostics
Engine-test page
Drum rotation functional check
Half self-test functional check
Plug/jack locations
Location of connectors
Locations of major components
General timing chart
General circuit diagram
Internal print-quality test pages
Clean the paper path
Print the configuration page
Print-quality troubleshooting tools
Repetitive defect ruler
Control panel menus
Touchscreen control panel
Setup menu
Fax Menu
Copy Menu
LCD control panel
Setup menu
Copy menu
Interpret control-panel messages
Control-panel message types
Control-panel messages
Clear jams
Solve paper feed or jam problems
The product does not pick up paper
The product picks up multiple sheets of paper
Frequent or recurring paper jams
Prevent paper jams
Clear jams from the input tray
Clear jams in the toner-cartridge area
Clear jams in the output bin
Clear jams in the document feeder
Solve paper-handling problems
Solve image-quality problems
General print-quality issues
Copy print-quality problems
Scan-quality problems
Prevent scan-quality problems
Solve scan-quality problems
Clean the product
Clean the pickup roller and separation pad
Clean the paper path
Clean the toner-cartridge area
Clean the exterior
Check the scanner glass for dirt and smudges
Clean the pickup rollers and separation pad in the document feeder
Solve performance problems
Solve connectivity problems
Solve direct-connect problems
Solve wired network problems
Poor physical connection
The computer is using the incorrect IP address for the product
The computer is unable to communicate with the product
The product is using incorrect link and duplex settings for the network
New software programs might be causing compatibility problems
The computer or workstation might be set up incorrectly
The product is disabled, or other network settings are incorrect
Solve wireless network problems
Wireless connectivity checklist
The product does not print after the wireless configuration completes
The product does not print, and the computer has a third-party firewall installed
The wireless connection does not work after moving the wireless router or
Cannot connect more computers to the wireless product
The wireless product loses communication when connected to a VPN
The network does not appear in the wireless networks list
The wireless network is not functioning
Perform a wireless network diagnostic test
Reduce interference on a wireless network
Service mode functions
Secondary service menu
Open the secondary service menu
Secondary service menu structure
Product resets
Restore factory settings
NVRAM initialization
Solve fax problems
Check the hardware setup
Faxes are sending slowly
Fax quality is poor
Fax cuts off or prints on two pages
Product updates

Appendix A: Service and support
Hewlett-Packard limited warranty statement
HPs Premium Protection Warranty: LaserJet toner cartridge limited warranty statement
HP policy on non-HP supplies
HP anticounterfeit Web site
Data stored on the toner cartridge
End User License Agreement
Customer self-repair warranty service
Customer support

Appendix B: Product specifications
Physical specifications
Power consumption, electrical specifications, and acoustic emissions
Environmental specifications

Appendix C: Regulatory information
FCC regulations
Environmental product stewardship program
Protecting the environment
Ozone production
Power consumption
Toner consumption
Paper use
HP LaserJet print supplies
Return and recycling instructions
United States and Puerto Rico
Multiple returns (more than one cartridge)
Single returns
Non-U.S. returns
Material restrictions (LaserJet Pro MFP M125-M126 series)
Material restrictions (LaserJet Pro MFP M127-M128 series)
Disposal of waste equipment by users
Electronic hardware recycling
Chemical substances
Material Safety Data Sheet (MSDS)
For more information
Declaration of conformity (M125a-M125ra)
Declaration of conformity (M125nw-M126nw)
Declaration of conformity (M127fn-M128fn)
Declaration of conformity (M127fp-M128fp)
Declaration of conformity (M127fw-M128fw)
Safety statements
Laser safety
Canadian DOC regulations
VCCI statement (Japan)
Power cord instructions
Power cord statement (Japan)
EMC statement (Korea)
Laser statement for Finland
GS statement (Germany)
Substances Table (China)
SEPA Ecolabel User Information (China)
Restriction on Hazardous Substances statement (Turkey)
Restriction on Hazardous Substances statement (Ukraine)
Eurasian Conformity (Belarus, Kazakhstan, Russia)
Additional statements for telecom (fax) products
EU Statement for Telecom Operation
New Zealand Telecom Statements
Additional FCC statement for telecom products (US)
Telephone Consumer Protection Act (US)
Industry Canada CS-03 requirements
Vietnam Telecom wired/wireless marking for ICTQC Type approved products
Additional statements for wireless products
FCC compliance statement-United States
Australia statement
Brazil ANATEL statement
Canadian statements
Products with 5 GHz Operation Industry of Canada
Exposure to Radio Frequency Radiation (Canada)
European Union regulatory notice
Notice for use in France
Notice for use in Russia
Mexico statement
Taiwan statement
Korean statement
Vietnam Telecom wired/wireless marking for ICTQC Type approved products