How do i clean drum wire - Brother MFC 7840W Printer

Gregory, First remove the drum unit. Then remove the Charge unit. located about the drum on the drum cartridge (Not Inside the Machine) Then remove scortron grid push the front in to release you then have access to the charge wire this model may have the Charge comb type be care the combs are sharp if they are wires be gentle and use a eraser to gentle clean the wires they are very thin. During the copy process the wire/comb applies a HV charge on the drum prior to the image from the mirrors being place on the drum before the paper arrives underneath the drum.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/normanj_7893313f0751935f

with the drum facing you, there's a green tab on the drum away from you. Slide it left & right several times to remove dust on the corona wire.

Remove the old drum unit,remove the drum and the drum cleaning blade,clean the charge corona wire and grid,install the new drum and drum cleaning blade,clean the image transfer /separator corona wire,clean the optical parts(mirrors ,lens,glass)clean the AIDC sensoe located under OPC drum,reinstall the drum unit in the copier,enter in the technical Rep mode,place 5 sheets A3 paper on the original glass and perform F5 AIDC sensor(Auto image density control).

Drum Error:

The corona wire on the drum unit
needs to be cleaned.
Clean the corona wire on the drum unit.
(See Cleaning the corona wire on page 122.)

or

The drum unit has reached the
end of its life.
Replace the drum unit.
(See Replacing the drum unit on page 130.)

and/or

Open the front cover
press Clear/Back
Press Start, then 00
after the screen show "accepted"
close the front cover and you are good to go.

Has two situations:

1. The corona wire on the drum unit needs to be cleaned.Clean the corona wire on the drum unit.
2. The drum unit has reached the end of its life. Replace the drum unit.

Your cartridge has two sections, the drum and the toner section. The corona wire is on the drum section. There should be a blue tab on the top left hand side of your drum unit. Slide this tab across the cartridge one or two times, returning the tab to its original position. There should be an arrow on the blue tab that will match up with an arrow on the drum unit when the tab is in its resting position. Performing this action cleans the corona wire inside the cartridge. If this doesn't fix it you may need to purchase a new drum unit.

Did you replace the drum or the toner cart? The drum has a blue lever that you slide back and forth around 20 times to clean the corona wire. I sometimes use a cotton swab with alcohol to gently clean this wire as well.

I was getting the clean the corona wire problem message even after repeated cleanings.  Before this problem occured the toner light was flashing warning of low toner. When I got the clean the wire pop up the toner light was on all the time indicating the toner was depleated.  So, I thought I would try replacing the toner cartridge and see what happened. I opened the new toner box and noticed on the foil packege specific instructions to clean the corona wire when installing the new toner.  I installed the new toner and cleaned the wire one more time. I then reinstalled the drum and toner assembly into the printer and the clean the corona wire message did not come up again.  The printer now works fine. 

The drum is the larger plastic unit that slides out an the toner cartridge fits into it. The corona wire is the very fine wire at the front top of the drum. Just slide the little cleaning tab back and forth.

the drum unit may have a full waste toner hopper, I am not sure but defintely do not clean, or touch the drum, you may touch the the drum unit which has a corona wire which occasionally may need cleaning by running a wand across it. there should be a colored clip that will slide back and forth on the drum catridge to clean it.sorry i couldn't be more helpful without actually seeing it.


Thank You,

Mikey