Xerox C2424 Service Manual - Page 275

Analyzing Service Test Prints A variety of test prints are available in the Hidden Service Menu to aid in determining the quality of output from the system and to assist in troubleshooting problems. This section shows how to select and analyze all test prints available to the system. To access the Test Print menu, see the "Hidden Service Menu" on page 4-2. Note Defects revealed by the prints may not occur in the course of ordinary printing. In servicing the system, you should minimize the defects shown by the prints but not necessarily eliminate them. Test Print Examples 1: Weak/Missing Jet This print shows the jets not outputting enough ink, if any, compared to its neighboring jets. Note that the yellow jets' bands have a small amount of cyan ink added to them. This tints them green to make them more visible. Look for: No interlacing is used in this print: expect light/dark variation between jets. Use Look for much lighter colored vertical bands in the horizontal bars. Weak jets in the yellow band are distinguished by a cyan tint. Causes: A jet may be partially clogged. Perform printhead clean/purge cycles on the printhead to remove contaminants from the poorly-performing jet. Run a jet fix cycle by downloading the snippet from the customer support site. If jet substitution mode is required, see "Jet Substitution Mode" on page 6-12. Test the purge system and the wiper blade performance. Turn the system off for 4 to 6 hours (or overnight, if practical). Then perform a clean/ purge cycle again. There may be a problem in the purge pump assembly or the wiper assembly may not be compliant. Verify that the printer is using Xerox ink. Follow the instructions on the "Printhead Troubleshooting Checklist". 74 75 76 77 78 79 80 Weak jet s2424-092 Image-Quality Troubleshooting 5-35