What is the Brother Corona Wire

It is a very fine wire found at the top of the drum unit right next to the blue tab.

The electrically charged wire in a laser printer attracts toner from the drum onto the paper. Because of this process the wire can attract itself toner and thereby reducing the electric charge on the wire can produce a poor quality image. Brother suggest to slide the blue tab back and forth to clean the wire. Make sure the tab

is locked  in the home position, otherwise a vertical line can be produced.

Every time a toner is replaced clean the corona wire. If the Drum LED is ON after following the above steps, try cleaning the metal contacts (see below) with a dry lint-free soft cloth.

 

If the Paper LED is flashing after you cleaned the corona wire, please check to see if there is no paper jam. Or click here for more suggestions

If the Paper LED is flashing after you removed the jammed paper, turn on and off the machine power switch. If the Paper LED is still flashing click here for suggestions

If the Drum LED is flashing after you cleaned the corona wire, the drum unit is near the end of its life. We recommend that you obtain a new drum unit to replace the current one

Tip: 
This product below makes the job of blowing toner off the corona a thorough job, then use the above method of sliding the tab. You will also find the duster useful for blowing toner dust out of the printer where it will collect over time. Of course  while you are at it....blow out your keyboard. You'll be surprised by the accumulation of debris under the keys.