Dealers and customers report problems with the LaserWriter and LaserWriter Plus
when printing dark areas. Dark areas of print are consistently lighter than on
other Laserwriters printing the same document. Changing the toner cartridge
has little effect. Further, the laser power adjustment shows that everything
is within recommended specifications.
A Level 1 technician can solve the problem using Technical Procedures. First,
remove the transfer corona assembly and look at the underside. You will notice
that there are two clear plastic screws, one at each end of the assembly.
These screws raise or lower the corona wire 0.5 mm per revolution. Raising the
wire increases the charge that attracts the toner to the paper from the drum
thereby increasing the amount of toner pulled from the drum onto the toner.
Important: If problems earlier in the printing process restrict the amount of
toner deposited on the photosensitive drum, then this adjustment will have no
effect on the print quality. Therefore, be sure to troubleshoot the printer
thoroughly and rule out other possible causes before performing this
adjustment.