Lexmark C720 User's Guide - Page 136

Print quality problems Problem Action Print is too light, or printed images or characters have voids or dropouts. Make sure the front, top, and rear doors are closed completely. Make sure you're using recommended paper or other media. Use media from a new package. Make sure you have selected the correct Paper Type setting for the media you're using. If you suspect a toner cartridge is low on toner, remove the appropriate cartridge and gently shake it back-and-forth to distribute the toner evenly. Reinsert the cartridge and try printing the job again. Replace the toner cartridge that matches the color on the page that is too light or not present in the void areas. See Replacing the toner cartridge. Colored lines, streaks, or smudges appear on the printed page, or print appears blurred or unclear. Replace the toner cartridge that matches the color of the lines, streaks, or smudges on the page. See Replacing toner cartridges. Clean the photo developer discharger. See Cleaning the photo developer charger. Make sure the the drum cleaner is fully seated. See Replace the drum cleaner. The page has 100% coverage of Replace the toner cartridge that matches the color on the page. See one color. Replacing toner cartridges. Light lines or streaks appear on the printed page. Remove the toner cartridge that matches the color of the lines or streaks and gently shake it back and forth to distribute the toner evenly. Reinsert the toner cartridge and try printing the job again. Replace the toner cartridge that matches the color of the lines or streaks on the page. See Replacing toner cartridges. If the lines are black, you may need to replace the fuser. See Fuser and air filter for more information. Light lines or voids appear from the top of the page to the bottom of the page. Remove the photo developer cartridge and clean the dust from the photo developer cartridge discharger. (See Cleaning the photo developer charger.) Reinsert the photo developer cartridge and try printing the job again. The toner cartridge may be low on toner, remove the cartridge, shake it, and reinsert it. If the problem still occurs, replace the toner cartridge. See Replacing toner cartridges. Replace the photo developer cartridge. See Replacing the photo developer cartridge. 136