Xerox M20 - WorkCentre B/W Laser, Service Manual

Page: 88 / 314

December 2006
3-12 WorkCentre M20, 4118, FaxCentre 2218 Family
IQ7, IQ8
Image Quality
• PBA main (M20F), PL 1.10 Item 4.
• PBA main (4118), PL 1.15 Item 9.
• PBA main (2218), PL 1.20 Item 9.
6. Refer to REP 6.1. Lift out the unit - LSU. Clean the unit - LSU window, using a clean, lint-
free cloth. If necessary, install a new unit - LSU, PL 6.10 Item 1.
7. Refer to Wiring Diagram 1 (M20F) or Wiring Diagram 8 (4118/2218). Go to GP 1 Engine
Test Mode Entry. Perform test number 5 to check the MHV ADC read and THV ADC read
values. As necessary perform the following:
• Check the contact springs supplying the voltages to the ELA Unit - OPC drum set
and the wiring to the SMPS + HVPS (M20F) or HVPS (4118/2218).
• Install a new ELA Unit - OPC drum set, PL 9.10 Item 1.
• Clean any contamination on the ELA - toner unit set. If necessary, install a new ELA
- toner unit set, PL 9.10 Item 2.
8. Ensure the transfer roller contacts, which are housed within the PMO - housing terminal
MC2, PL 4.15 Item 2 are not deformed. If necessary install a new ELA HOU - frame main
assembly, PL 4.15 Item 1.
NOTE: The PMO - housing terminal MC2 is not spared.
9. Install new components as necessary:
• SMPS + HVPS (M20F), PL 1.12 Item 4.
• HVPS (4118), PL 1.15 Item 10.
• HVPS (2218), PL 1.20 Item 10.
IQ8 Dark Image RAP
Use this RAP when the machine produces dark images in all modes.
Procedure
WARNING
Switch off the electricity to the machine. Disconnect the power cord from the customer
supply while performing tasks that do not need electricity. Electricity can cause death or
injury. Moving parts can cause injury.
NOTE: If necessary, refer to GP 20 for the acronym list and cross reference lists of more com-
monly recognised part names.
Perform the following:
1. Ensure that the paper tray settings match the paper or media size in the trays.
2. Go to GP 3, Service Mode Entry. Scroll to System Admin Tools/Maintenance. Perform the
Adjust Shading procedure. If the Shading Test fails, install new components as neces-
sary:
NOTE: Refer to GP 6 Maintenance for additional information about the shading test.
• ELA HOU - CCD module, PL 14.11 Item 16.
• CBF signal - CCD FFC, PL 14.11 Item 17.
• ELA HOU - scanner assembly, PL 14.10 Item 1.
• PBA main (M20F), PL 1.10 Item 4.
• PBA main (4118), PL 1.15 Item 9.
• PBA main (2218), PL 1.20 Item 9.
3. (M20F) Refer to Wiring Diagram 1. Perform the following:
• Check the spring contacts and the wiring to the SMPS + HVPS.
• If necessary, install a new SMPS + HVPS, PL 1.12 Item 4.
4. (4118/2218) Refer to Wiring Diagram 8. Perform the following:
• Check the spring contacts and the wiring to the HVPS.
• Install new components as necessary:
– HVPS (4118), PL 1.15 Item 10.
– HVPS (2218), PL 1.20 Item 10.
5. Print a test pattern. For example, print the help list from the menu. Install new components
as necessary:
• PBA main (M20F), PL 1.10 Item 4.
• PBA main (4118), PL 1.15 Item 9.
• PBA main (2218), PL 1.20 Item 9.