In order to solve problems that may occur while loading cartridges, it is helpful to understand the basic principle in which a printer works.
Printing consists of 6 stages - cleaning, conditioning, writing, developing, transferring, and fixing. The following explains each stage and the mechanical malfunctions that may occur in each stage.

An image appears on the center of the OPC drum. The aluminum cylinder of the drum is coated with a nontoxic, material that is sensitive to light.

1) Cleaning
2) Conditioning
3) Writing
4) Developing
5) Transferring
6) Fixing

1) Cleaning

Cleaning is the first stage in printing an image.
This stage consists of physical and electric cleaning in preparation of the image setting on the OPC drum. The cleaning blade (wiper blade) and recovery blade are involved in the physical cleaning process. First, the wiper blade removes leftover toner from the drum. Next, the recovery blade catches the residual toner and empties it into a waste bin.
The electric cleaning of the OPC drum removes images that are still leftover on the drum by the erase lamp (corona wire) or PCR (Primary Charge Roller). If these devices are worn down or damaged, this made result in vertical lines on prints, blurry or unclear images, uneven distribution of ink, or ghosting.

2) Conditioning

Once the drum has been cleaned, conditioning is performed so that the image read from the LSU (Laser Scanning Unit) can beamed onto the drum with a laser beam.
The corona wire or PCR sends electricity (-600V to -720V DC) to the drum surface.
If the applied voltage is incorrect, an incorrect image may be printed. (Shadows or lines may appear on the printed image.) However, although lines caused by corona wire malfunctions may appear evenly, problems caused by blade malfunctions are not even and may even cover the entire sheet of paper.

3) Writing


A latent image is formed on the areas of the drum surface that have been targeted by the laser. The drum is made of an aluminum cylinder that conducts electricity. Because the cylinder is coated with a photosensitive substance, an image forms on the surface when lighted with a laser. This image area draws toner (electrically positive) to itself in the next stage.

4) Developing

The latent image finally appears on the drum surface in the stage.
Four key components and substances are involved in this process - toner, development roller, doctor blade, and AC/DC electricity. The development roller sends toner particles to the drum surface while the doctor blade controls the toner used. The HVPS (High Voltage Power Supply) supplies the development roller (MAC) with AC/DC electricity. If a malfunction occurs in this process, ghosting, blurring, or massing of ink may occur.

5) Transferring

The toner on the drum image is transferred onto the paper in the transferring stage. Paper passes beneath the OPC drum and above the transferring device. A positive current flows through the transferring device, pulling the toner on the OPC drum onto the paper.
Damage or malfunction of this device causes faint images or results in a waste of toner.

6) Fixing

The toner-covered paper passes through the heating roller and pressure roller in this stage. The toner is fixed onto the paper with high temperature heat and high pressure. The heating roller releases heat exceeding 180 degrees and is made of a aluminum cylinder coated with Teflon.
The pressure roller is made of firm silicon rubber. This roller applies firm pressure to the heating roller and melts the toner particles on the paper with high temperature heat. If the fixing device is damaged this will lead to toner ink massing up in one spot or side, blurry or unclear images, or ghosting (a phenomenon where a double image appears).

1. Sealing íŠ Toner (Injection) íŠ Mag Roller (Processing) íŠ Assembly
  TONER HOPPER ASSEMBLY
2. Drum replacement íŠ Wiper Blade replacement íŠ PCR Roller (Processing) íŠ Assembly
  WASTE BIN ASSEMBLY