- HP All-in-One Printer Manual

Q2431-90912 Chapter 7 Troubleshooting 325
Repetitive defects troubleshooting
Defects on printer rollers can cause image defects to appear at regular intervals on the page.
These defects appear at regular intervals that correspond to the circumference of the roller
causing the defect. Measure the distance between defects that recur on a page. Use table 75 or
the repetitive defect ruler (figure 207) to determine which roller is causing the defect. To resolve
the problem, try cleaning the roller first. If the roller is still dirty after cleaning or if it is damaged,
replace the indicated part.
CAUTION Do not use solvents or oils to clean rollers. Instead, rub the roller with lint-free paper. If dirt is
difficult to remove, rub the roller with lint-free paper dampened with water.
Note Defects on the tray pickup rollers or the tray 1 pickup roller do not cause a repetitive defect.
Defects on these rollers cause a defect to appear only on the leading edge of the image.
Figure 207. Repetitive defect ruler
Table 75. Repetitive defects
Roller Distance between defects Replacement part
Primary charging roller 37.7 mm (1.5 inches) print cartridge
Developer roller* 62.8 mm (2.5 inches) print cartridge
Fuser 75.0 mm (2.95 inches; HP LaserJet 4200)
94.0 mm (3.75 inches; HP LaserJet 4300)
Fuser
Photosensitive drum 94.2 mm (3.75 inches) print cartridge
*The developer roller circumference is 62.8 mm (2.5 inches). This defect will most likely repeat at intervals
of 54.0 mm (2.125 inches) because of the way it is geared.
First occurrence of the defect
37.7 mm (1.5 inches) primary charging roller
54.0 mm (2.125 inches) developer roller (see note)*
62.8 mm (2.5 inches) developer roller (see note)*
94.0 mm (3.75 inches) fuser (HP LaserJet 4300)
94.2 mm (3.75 inches) photosensitive drum
*Note: The developer
roller circumference is
62.83 mm (2.5 inches).
This defect will most
likely repeat at
intervals of 54.0 mm
(2.15 inches) because
of the way it is geared.
75.0 mm (2.95 inches) fuser (HP LaserJet 4200)