If you have print quality problems, clean the corona wire as follows:

1. Turn off the printer power switch.
   
   

   

   
   

2. Fully open the top cover by lifting up on the handle (1).
   
   

   

   
   

3. Take out the drum unit and toner cartridge assembly.
   
   

   

   
   

   • We recommend that you place the drum unit and toner cartridge assembly on a clean, flat surface with a sheet of disposable paper or cloth underneath it in case you accidentally spill or scatter toner.
   • To prevent damage to the printer from static electricity, DO NOT touch the electrodes shown in the illustration.
     
     

     
4. Clean the primary corona wire inside the drum unit by gently sliding the green tab from left to right and right to left several times.
   
   

   Be sure to return the tab to the home position () (1). If you do not, printed pages may have a vertical stripe.

   
   
   

   

   
   
5. Slide the drum unit and toner cartridge assembly into the printer. Make sure that you match the toner cartridge color to the same color label on the printer.
   
   
   C- Cyan, M- magenta, Y- Yellow, K- Black
   
   

   

   
   
6. Repeat steps 3 to 5  to clean each of the remaining corona wires.
   
   
7. Close the top cover of the printer.
   
   

   

   
   
8. Turn the printer power switch back on.