Dropouts (continued) Faded Print/Bubbles C4170-90959 Image Formation Troubleshooting 119 Possible Cause Action Paper does not meet specifications. The paper moisture content, conductivity, or surface finish may not work correctly with the electrophotographic process. Try a different paper lot. See “Media Troubleshooting” (page 129). Engine Controller defective (low primary voltage or incorrect high voltage). Replace the Engine Controller. Transfer Roller defective. Replace the Transfer Roller. See also “Blank Spots” (page 114) Hot offset after running narrow or thin media. Let engine cool and retry printing. Possible Cause Action 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. See “DC Bias Voltage Contacts Replacement” (page 245) EconoMode is on. EconoMode saves toner by reducing the dot density. This may appear to be a print quality problem in some cases. Turn EconoMode off. Toner supply is low. Shake the cartridge gently to redistribute the toner, or replace the cartridge. Paper does not meet specifications. The moisture content, conductivity, or surface finish may not work correctly with the electrophotographic process. Try a different paper lot. See “Media Specifications” (page 28)).