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C4121A LaserJet 4000TN Printer

HP LaserJet 4000TN (C4121A)

MFG Part Number: C4121A

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HP LaserJet 4000 printer series service manual

C4121A Service Manual

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Manual contents and shortcuts

Printer Description

Printer Features

Model and Serial Numbers

Site Requirements

Space Requirements

Paper Specifications

Supported Types of Paper

Guidelines for Using Paper

Card Stock and Heavy Paper

Safety Information

Canadian DOC Regulations

Laser Safety Statement

FCC Regulations

Laser Statement for Finland

Environmental Product Stewardship

Service Approach

Service Approach

Parts and Supplies

Ordering Information

Helpful Documentation

Exchange Program

Phone Numbers for Ordering

Technical Assistance

Toner Cartridge Information

Warranty Statement

Printer Operation

Using the Control Panel

Control Panel Layout

Control Panel Lights

Control Panel Keys

Settings and Defaults

Control Panel Menus

Information Menu

Paper Handling Menu

Print Quality Menu

Configuration Menu

EIO Menu (Networked Printers)

Setting the Page Count, Maintenance Count, and Ser...

Clear Event Log

Cold Reset Paper

Testing the Printer

Resetting the Printer

System Configuration

MS-DOS System Configuration

Parallel DOS Commands

Serial MS-DOS Commands

Printer I/O Configuration

Serial Configuration

Printer Maintenance

Cleaning the Printer and Accessories

Cleaning Spilled Toner

Preventative Maintenance

Expected Life of Components

Reset Maintenance Count

Functional Information

Printer Subsystems

Power Supply System

AC/DC Power Distribution

Overcurrent Overvoltage Protection

High Voltage Power Distribution

Engine Controller Subsystem

Toner Cartridge Detection

Engine Controller Board Inputs and Outputs

Laser and Scanner Drive

Engine Test Print

Paper Motion Monitoring and Control

Solenoids, Sensors, Clutches, and Switches

Formatter System

Resolution Enhancement technology (REt)

Random Access Memory (RAM)

Memory Enhancement technology (MEt)

Image Formation System

Toner Cartridge

Photosensitive Drum

Writing the Image

Developing the Image

Transferring the Image

Image Fusing/Variable Fusing Temperature

Paper Feed System

Clutches and Sensors

Printing from Tray 1

Printing from Tray 2

Printing from the Optional 500-sheet Tray

Envelope Feeder

Basic Sequence of Operation

Removing and Replacing Parts

Removal and Replacement Strategy

Removing Covers

Rear Right Side Cover

Left Side Cover

Front Right Side Cover

Rear Cover/Rear Output Bin

Removing Assemblies

Formatter Cage Assembly

Output Assembly

Transfer Roller

Tray 1 Pickup Roller

Tray 1 Pickup Assembly

Right Side Toner Cartridge Guide

Registration Assembly

Paper Feed Assembly

Delivery Drive Assembly

Separating the Engine Module from the Paper Feed M...

Engine Controller Board

Paper Feed Rollers

Separation Rollers

Paper Feed Module Plate

Paper Feed Module Gear Train Assembly

Paper Feed Module Side Rails

Lower Paper Feed Module Plate (HP LaserJet 4000 T/...

PCA Cover (HP LaserJet 4000 T/4000 TN)

PCA Cover (HP LaserJet 4000/4000 N)

Troubleshooting

Troubleshooting Process

Troubleshooting Flowchart

Troubleshooting Flowchart (Continued)

Troubleshooting the Printing System

Preliminary Operating Checks

Printer Messages

General Paper Path Troubleshooting

Information Pages

Image System Troubleshooting

Interface Troubleshooting

AUTOEXEC.BAT Standard Configurations

Reference Diagrams

Locations of Components

Engine Controller Board

Paper Size Detection Switches

Sensors and Thermistor

Solenoids and Clutch

Parts and Diagrams

How To Use the Parts Lists and Diagrams

Accessories and Supplies

Common Screws and Replacement Cables

Illustrations and Parts Lists

Alphabetical Parts List

Numerical Parts List

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