HP LaserJet 9040/9050 Service Manual - Page 252

Table 29. Image defects Problem Cause Solution Black page The high-voltage power supply connections are contaminated. z Clean the high-voltage power supply terminals. z Clean the high-voltage springs where they contact the print cartridge. The high-voltage power supply is z installed incorrectly. Note If the high-voltage power supply z was removed and replaced, it might not be seated correctly. Remove the high-voltage power supply and check the connectors and ribbon cable for damage. Reseat the high-voltage power supply, and make sure to fully seat the connectors and ribbon cable correctly. Defective primary charging roller. z Replace the print cartridge. The laser drive circuitry is damaged z Replace the laser/scanner assembly and on the DC controller board so that the DC controller board, and the formatter, if laser is always on. necessary. White page The print cartridge is out of toner. z Replace the print cartridge. The laser shutter is defective. z Check the laser shutter for correct operation when closing the front door with the print cartridge installed. Transfer charging roller voltage does z Replace the transfer roller assembly if not exist. necessary. Developing bias does not exist. z Clean the high-voltage power supply contacts. z Replace the high-voltage power supply. The laser/scanner cable assembly is z Replace the laser/scanner cable defective. assembly. Blank spots The media does not meet printer z specifications or is stored incorrectly. z z Print a few more pages to see if the problem corrects itself. Turn over the stack of media in the tray. Also try rotating the media 180°. If the media does not meet HP specifications, replace the media. The transfer charging roller is contaminated of deformed. z Replace the transfer charging roller. Also see "Dropouts" on The print cartridge is defective. page 238. z Replace the print cartridge. 236 Chapter 7 Troubleshooting