HP LaserJet 5000 Service Manual - Page 276

Table 7-11. Blank Page (continued) Possible Cause Action DC Controller PCA is Replace the DC Controller PCA. defective. The DC Controller supplies the proper voltage to the High Voltage Power Supply PCA. No Developing Bias. 1. Clean the High Voltage Power Supply contacts. With no Developing Bias charge, toner is not attracted to the drum. 2. Replace the Engine Controller Board. No drum ground path. With no ground path the drum cannot discharge. The negative charge on the drum repels toner, and leaves a white page with bubble print. 1. Check the drum ground. 2. Replace the Engine Controller Board. Defective Laser Scanner Cable Assembly. Low-level signals exchanged between the Laser Scanner Assembly and the Engine Controller Board may be affecting laser output. Replace the Laser Scanner Cable Assembly. Table 7-12. Blank Spots Possible Cause Action Paper does not meet printer specifications or is stored improperly. 1. Print a few more pages to see if the problem corrects itself. 2. Turn over the stack of paper in the tray. Also try rotating the paper 180°. 3. Check the paper (or other print media) type and quality. Replace the paper, and advise the customer to use the recommended paper and store it properly. Defective Toner Cartridge. Replace the Toner Cartridge. EN Troubleshooting the Printing System 7-55