HP 8150dn Service Manual - Page 679

Table 7-29. Image Skew (continued) Possible Cause Recommended Action 3. Paper lot is bad. Paper that is Try a different paper lot (see HP manufactured poorly or inconsistently LaserJet Printer Family Print Media or that has too smooth or too rough a Guide). surface texture can cause an image skew problem. 4. Pickup and/or Registration Rollers Inspect all paper path rollers, looking are worn. Paper is not being picked for wear, cracks, or glazing. Replace up consistently. the worn rollers. Table 7-30. Bubble Print Possible Cause Recommended Action 1. Photosensitive drum inside toner cartridge is not grounded. 1. Check for proper mounting of the High Voltage Power Supply (HVPW) and the HVPS ground contacts on the toner cartridge. 2. Check for proper seating of toner cartridge. 3. Replace the toner cartridge. 2. Toner cartridge is leaking. Replace the toner cartridge. 3. Paper does not meet Try a different paper lot (see HP specifications. The moisture content, LaserJet Printer Family Print Media conductivity, or surface finish may not Guide). work correctly with the electrophotographic process. 4. High Voltage Power Supply is defective. Replace the High Voltage Power Supply. See "High Voltage Power Supply (HVPS)" on page 319 for instructions. 662 Chapter 7 TroubleshootingC4265-90907