Follow the steps below to clean the corona wire.

1. Make sure that the machine is turned on.
2. Press the front cover release button and pull open the front cover.
   
    
    
3. Hold the blue handle of the drum unit. Pull the drum unit out until it stops.
   
    
    
4. Hold the handle of the toner cartridge and gently push it toward the machine to unlock it. Then pull it out of the drum unit. Repeat this for all the toner cartridges.
   
    
    
5. Clean the corona wire inside the drum unit by gently sliding the blue 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.

    

    

   
    
6. Repeat step 5 to clean each of three remaining corona wires.
7. Hold the handle of the toner cartridge and slide the toner cartridge into the drum unit then gently pull it toward you until you hear it click into place. Make sure that you match the toner cartridge color to the same color label on the drum unit. Repeat this for all the toner cartridges.
   
    
    
8. Push the drum unit in until it stops.
   
    
    
9. Close the front cover of the machine.