HP LaserJet M9040/M9050 Service Manual - Page 407

Table 7-13 Image defects (continued) Problem Cause Solution Toner specks Contamination exists in the product. Print a few more pages to see if the problem persists. Clean the inside of the product, or use a cleaning page. The media fails to meet product specifications or is stored improperly. Print a few more pages to see if the problem persists. Turn the stack over in the tray, or rotate the stack 180° Use media that meets product specifications. The product is printing alternating small To alternate small and standard media, and standard media. from the paper Print Quality menu, set Small Paper Mode to Slow. Vertical black lines The print cartridge is defective. Replace the print cartridge. The fuser entrance guide is contaminated. Clean the guide. The fuser is scratched. Replace the fuser. The fuser film is worn. Set the fuser to a lower temperature mode. Replace the fuser. Vertical dots The static charge eliminator teeth are contaminated. Clean the static charge eliminator. Bad connection between the static charge eliminator and the high voltage power supply. Clean the contacts. If the problem persists, or if parts are damaged or deformed, replace them. The transfer charging roller is deformed Replace the transfer charging roller. or deteriorated. The high voltage power supply is defective. Replace the high voltage power supply. Vertical white lines The print cartridge is defective. Replace the print cartridge. The laser path is contaminated. Clean the laser path by removing the laser/scanner assembly and clean the lens. Replace the laser/scanner assembly. The fuser is defective. Check to see if maintenance is due by printing the supplies status page. Replace the fuser. ENWW Image-formation troubleshooting 389