HP Partner Learning Center

Disassembling an HP Color LaserJet Managed MFP E786DN printer requires technical knowledge and should be done carefully to avoid damaging internal components. Here is a general guide to help with the disassembly process, typically done for maintenance, repair, or component replacement.

Tools Needed:

• Phillips head
• screwdriver
• Flathead screwdriver or plastic pry tool
• Anti-static wrist strap (to avoid damaging electronic components)
• Tweezers (for small parts)

General Safety Precautions:

1. Power Off: Ensure the printer is turned off and unplugged from the power source before starting.
2. Remove Paper and Trays: Take out any paper in the trays and remove the paper trays themselves to make the internal components easier to access.
3. Handle with Care: Be careful when handling internal parts, as some may be delicate.

Step-by-Step Disassembly:

1. Remove the External Covers:

• Side Panels: Use a flathead screwdriver or a plastic pry tool to gently remove the side panels.
• Top Cover: After removing the side panels, unscrew and lift the top cover carefully.
• Front and Rear Covers: Unscrew the necessary screws at the front and rear of the printer. Use a flathead screwdriver to release the tabs holding the front cover in place. Remove it slowly to avoid damaging cables attached to the control panel.

2. Access the Toner Cartridges:

• Open the front panel, where the toner cartridges are housed.
• Remove the toner cartridges carefully by pulling them out of their slots.

3. Disassemble the Fuser Assembly:

• Locate the fuser assembly, which is responsible for applying heat to fuse the toner onto the paper.
• Unscrew the fuser unit and gently lift it out. Be cautious when handling it, as it can be sensitive to impact.

4. Remove the Scanner Assembly (if applicable):

• For multifunction models, remove the scanner bed by unscrewing the hinges connecting it to the body of the printer.
• Disconnect any ribbon cables or connectors attached to the scanner module.

5. Access the Main Circuit Board (Logic Board):

• Unscrew the metal shielding covering the main circuit board (logic board).
• Disconnect all cables and connectors attached to the board before removing it.
• Once the screws are removed, lift the circuit board out carefully.

6. Remove the Paper Path Components:

• Remove any rollers, paper feed components, and sensors by unscrewing and lifting them out carefully.
• Be mindful of small springs or sensors that may be attached.

7. Disassemble the Printer’s Internal Components:

• Continue by unscrewing other internal components like motors, sensors, and gears as needed.
• Take note of where each screw and component belongs to make reassembly easier.

Reassembly:

Reassembling the printer is the reverse process of disassembly. Ensure each part is cleaned, checked for damage, and properly reinstalled. Tighten screws and reconnect any cables or connectors securely.

Tips:

• Documentation: Take pictures at each stage of disassembly to help guide you during reassembly.
• Labeling: Keep screws and small parts organized and labeled to avoid confusion during reassembly.
• Consult Service Manual: If available, refer to the official HP service manual for your model, which provides detailed diagrams and specific instructions.

Warnings:

• Opening the fuser or other components can expose you to electrical risks or hot parts. Make sure the printer has cooled down before proceeding.
• Disassembly should ideally be performed by trained technicians, as improper handling may void warranties or lead to malfunction.

This disassembly practice is ideal for skilled technicians who are familiar with HP devices and intend to repair or replace specific parts.