HP LaserJet 4250 Service Manual - Page 404

Table 7-26 Loose toner or toner smear (continued) Possible cause Recommended action(s) The fuser is defective. The print will smear if the fuser does not heat sufficiently to bond the toner to the paper. Replace the fuser. See Fuser. The dc controller PCA is defective. The dc controller PCA regulates the fuser roller temperature. Replace the dc controller PCA. See Dc controller PCA. Table 7-27 Repeating defects and repeating images Possible cause Recommended action(s) The print cartridge or fuser is damaged. The circumference of the photoconductive drum inside of the print cartridge is 94.2 mm (3.7 inches). If the defect repeats at this interval, the defect is associated with the drum. Repetitive defects caused by the LJ 4300 fuser roller repeat at 94.0 mm (about 3.7 inches). Because the LJ 4300 fuser roller is only 2 mm (.07 inch) smaller than the photoconductive drum, distinguishing defects that are caused by the photoconductive drum from those that are caused by the LJ 4300 fuser roller can be difficult. 1 Inspect the drum for scratches or other damage. Replace the print cartridge for defects that repeat at 37.7 mm (1.5 inches), 62.8 mm (2.5 inches), 54.0 mm (2.1 inches), or 94.2 mm (3.7 inches). 2 Process a printer cleaning page. See Running the cleaning page manually. 3 If the problem persists, and the defect repeats at 75.0 mm (2.95 inches) or 94.0 mm (about 3.7 inches), replace the fuser (see Fuser). For more information about troubleshooting repeating defects, see Repetitive-defects troubleshooting. The rollers are dirty. A dirty roller in the paper path can cause a repetitive defect. Examine and clean (or replace) the rollers in the paper path. The media does not meet specifications. Try a different media type or quality. Preprinted form paper is used. Some preprinted forms (for example, letterheads) use an ink that cannot stand up to the high temperatures in the fuser. Check the media for type and quality. Replace the media, and advise the customer to use the HPrecommended media and to store it correctly. See Media specifications. 390 7 Troubleshooting