HP LaserJet 4250 Service Manual - Page 413

Table 7-38 Blank page (Continued) Image-formation troubleshooting Possible cause Recommended action(s) The software configuration is incorrect (intermittent problem). Make sure that the software program is not sending incorrect page-length requests or extra page-eject commands. The network configuration is incorrect. Some sharing devices on networks might generate a blank page as a printjob separator. Check with the network administrator. Multiple feeds are occurring. The printer might be feeding two or more pages at on time (intermittent problem). Remove the media from the tray and flex the stack in one direction and then the other to separate the pages. Do not fan the stack. Replace the stack in the tray. The sealing tape was left in the print cartridge. Remove the sealing tape. The print cartridge is empty or defective. Replace the print cartridge. The laser/scanner shutter door is not opening correctly. 1 Remove and reseat the print cartridge. 2 Verify that the laser/scanner shutter door can open correctly. If necessary, replace the laser/ scanner assembly. See Laser/ scanner assembly. No transfer-roller voltage is being generated. Without transfer-roller voltage, toner does not transfer correctly from the surface of the drum to the paper. Perform the half self-test functional check (see Half self-test functional check) to check the electrophotographic process. If necessary, replace the transfer roller. See Transfer roller . The high-voltage connector springs are dirty or damaged. The high-voltage connector springs protrude into the print cartridge cavity. Clean the springs if they are dirty. Replace the springs if they are damaged or missing. No drum ground path exists. When no drum ground path exists, the drum cannot discharge. The negative charge on the drum repels toner, and leaves a nearly-white page (possibly with bubbled print). Check the drum ground that runs from the contact point in the center of the print drum. The high-voltage circuit is defective. Replace the power-supply assembly. See Power supply. The laser/scanner cable is defective. Low-level signals that are exchanged between the laser/scanner assembly and the dc controller PCA might be affecting the laser output. Replace the laser/scanner cables. 399