MJ Sipes

Thank you for the information, especially the service manual that I have saved.

We love the Brother MFC-L3770CDW multifunction printer, in fact we have 7 of them at work. One of them has a continuing error that either asks for drum replacement or corona wire cleaning. Even if corona wire is cleaned, the error will not clear. The drum units are only about 30% used. I have found the solution to be some combination of pulling out and placing back the toner/drum units to insure good electrical point contact. All contact points have been cleaned as well. If that method does not work, I manipulate the fins hanging down under the cover. Some combination of this work will typically cause the printer to clear error message and start printing again. When it first occurred a short time after warranty expired the certified Brother repair technician was told to replace the power unit to provide proper power supply to the drum units. It happen again within the month. No front line Brother online technician has a clue how to address the issue. Has any one else ever experienced this phenomenon and know of a fix? I don't want to replace the drum units yet but that may be an answer.