Xerox 78xx Toner Motor Removal: A Comprehensive Guide

Replacing the magenta toner motor on your Xerox 7855 model is a critical maintenance task to ensure optimal printer performance. This step-by-step guide simplifies the process, helping you navigate the intricate steps involved in accessing and replacing the toner control unit.

Step 1: Initial Setup

Before beginning the replacement process, prepare the machine for disassembly:

1. Open the Front Cover: Start by opening the front cover to reveal the four toner cartridges.

2. Remove Toner Cartridges: Carefully take out all cartridges to ensure unrestricted access to internal components.
   

Step 2: Removing Covers and Screws

To access the toner control unit, various covers and screws need to be removed:

1. Back Covers:

   • Remove three specific covers at the back of the machine by pulling tabs or using the designated handles.

   • Unscrew two screws to detach the back panel and reveal the internal assembly.

2. Bottom Panel:

   • Unplug the connected cord and unscrew three screws to remove the bottom panel.

   • This step provides access to additional internal components.
     

Step 3: Accessing the Toner Control Unit

With the covers removed, focus shifts to the toner control unit:

1. Open the Back Door:

   • Detach cables and unscrew multiple screws to open the back door.

   • Ensure that all cables are clear to allow the door to open fully.

2. Remove the Circuit Board:

   • Unscrew and detach the circuit board by pressing two prongs to release it.

   • Disconnect any cables attached to the board.

3. Expose the Toner Control Unit:

   • Remove additional screws to detach the black cover and expose the toner control unit.
     

Step 4: Front-Side Components

To fully access and replace the toner motor, additional steps must be performed on the front side:

1. Remove the Cleaning Blade and Waste Container:

   • Slide these components out carefully to access the drum compartment.

2. Detach the Plastic Covers:

   • Unscrew the gray and blue plastic pieces to create space for removing the toner control unit.
     

Step 5: Removing the Toner Control Unit

The toner control unit is the primary focus of this process:

1. Detach Green Boards and Clips:

   • Remove four green boards and associated clips, ensuring the wires are separated from the unit.

2. Unscrew and Remove the Unit:

   • Take out all screws securing the unit and gently slide it out of position.
     

Step 6: Reassembly

Once the toner motor is replaced, reassemble the printer:

1. Reverse the Steps: Follow the disassembly steps in reverse to secure all components.

2. Test Functionality: Ensure all cables are properly connected and the printer is operational before closing the machine.
   

   
   

Tips for Safe Replacement

• Use Proper Tools: Equip yourself with a standard Phillips head screwdriver and a 5.5 screwdriver for specific screws.

• Handle Components Carefully: Avoid damaging sensitive parts, especially cables and clips.

• Follow the Video Guide: Refer to the detailed video for visual demonstrations of each step.