Xerox WorkCentre 5687 Series, Service Manual, Page: 1662 / 2320

August 2007
4-642
WorkCentre 5687 Family
ADJ 9.5
Repairs/Adjustments
ADJ 9.5 Optimize Dark and Light Grey Image
Purpose
Use this adjustment if the dark greys are too dark and / or light greys are too light.
Use this adjustment in combination with the changes made in IQ10 Image Quality Improve-
ment RAP.
Perform IQ3 Xerographics RAP before starting this adjustment.
NOTE: This procedure will only make a slight improvement to the image quality.
Initial Actions
• Ensure that all the image quality settings on the UI are at default.
• Make a copy of the customer document that shows the defect and keep as a reference.
• Enter dC606 Print Test Patterns and print internal test pattern 15.
• Exit diagnostics, GP 1.
• Place the test pattern 15 on the platen glass with the dark bands to the right and the light
band to the left. Make a copy.
• Compare the copy with the test pattern 15, Figure 1.
– If the sections 5 - 7 look the same as each other then the machine has a problem
with poor shadows / dark greys. Go to the Poor Shadows Adjustment.
– If section 1 looks white then the machine has a problem with poor highlights / light
greys. Go to the Poor Highlights Adjustment.
• For 32-38 ppm machines only. Some machines suffer from poor shadows and poor
highlights. In such cases install the ROS filter and optimize poor shadows first. Installation
of the ROS filter will improve dark grey performance at the expense of slight degradation
of the light grey performance.
Then perform the poor highlights adjustment which, will attempt to restore the highlights.
If the highlights are unacceptable, then do not install the ROS filter.
Poor Shadows Adjustment
1. For 32-38 ppm machine only. Install the ROS filter kit, 604K31480.
2. Enter dC131 NVM Read / Write location 06-001 Light Level and reduce the value by 200.
• 32-38 ppm machines. Ensure that the value is between 3000 and 6000.
• 45-55 ppm machines. Ensure that the value is between 1650 and 2250.
• 65-87 ppm machines. Ensure that the value is between 1800 and 2400.
3. Enter dC606 Print Test Patterns and print test pattern 15.
4. Exit diagnostics, GP 1.
5. Place the new printed test pattern 15 on the platen glass and make one copy.
6. If the copy has poor shadows, then go to the next step.
If the copy has good shadows, then go to the Poor Highlights Adjustment.
7. Enter dC131 NVM Read / Write at location 06-001 Light Level and reduce the value by
200. Reduce the value in increments of 200 until good shadow is achieved.
• 32-38 ppm machines. Do not reduce the value below 3000.
• 45-55 ppm machines. Do not reduce the value below 1650.
• 65-87 ppm machines. Do not reduce the value below 1800.
8. Enter dC606 Print Test Patterns and print internal test pattern 15
9. Exit diagnostics, GP 1.
10. If the copy has poor highlights, then go to the Poor Highlights Adjustment.
If the highlights are good, then go to the Final Image Quality Check.
Poor Highlights Adjustment
1. Enter dC131 NVM location 09-003 Charge Grid and reduce the value by 25.
• 32-38 ppm machines. Ensure that the value is between 350 and 430.
• 45-55 ppm machines. Ensure that the value is between 350 and 430.
• 65-87 ppm machines. Ensure that the value is between 350 and 420.
2. Enter dC606 Print Test Patterns and print internal test pattern 15.
3. Exit diagnostics, GP 1.
4. Place the new printed test pattern 15 on the platen glass and make one copy.
5. If the copy has poor highlights, then go to the next step.
If the highlights are good, then go to the Final Image Quality Check.
6. Enter dC131 NVM. Location 09-003 Charge Grid and reduce the value by 25. Reduce the
value in increments of 25 until good highlights is achieved.
Do not reduce the value below 350.
7. Enter dC606 Print Test Patterns and print internal test pattern 15.
8. Exit diagnostics, GP 1.
9. Place the new printed test pattern 15 on the platen glass and make one copy. The copy
quality is optimized.
Final Image Quality Check
1. Enter dC606 Print Test Patterns and print internal test pattern 15.
2. Exit diagnostics, GP 1.
3. Place the new printed test pattern 15 on the platen glass and make one copy. The image
quality is optimized.
4. Make a copy of the customer document and compare it with the initial copy. Check that
the image quality has improved.
5. Run a variety of jobs to confirm that the changes made have not introduced other copy
quality problems.
6. Record any NVM changes in the machine log book.
7. Perform NVM Save and Restore to the resident diskette, GP 5.