Iq1 Blank Copies Rap; Iq2 Black Copies From The Scanner Rap - Xerox WorkCentre M20 Service Manual

IQ1 Blank Copies RAP

Use this RAP when the machine produces blank copies.
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.
Determine the source of the problem. Make a print. Make a copy.
If the fault appears only in the copy mode, perform the following:
1. Ensure the scanner cover is closed. Room illumination can be transmitted through thin
originals.
2. Go to GP 6, Maintenance, and perform the Adjust Shading procedure.
If the fault appears in all modes, perform the following:
1. Examine the ELA - toner unit set, PL 9.10 Item 2 and the ELA - OPC unit set, PL 9.10
Item 1. Ensure they are free from all packing or sealing material.
2. Shake the ELA - toner unit set. If there is a slight improvement in the image, the ELA -
toner unit set is empty. Install a new ELA - toner unit set, PL 9.10 Item 2.
3. Go to GP 1 Engine Test Mode Entry and perform the LSU tests, test 1.
4. Perform the following as necessary. Refer to Wiring Diagram 3:
• The LSU is supplied with +5V through the CBF - harness. Enter GP 1 Engine Test
Mode Entry. Use the sensor test to check the CBF - harness; switch micro.
Check that both micro switches in the CBF - harness; Switch Micro are switching;
one controls the +5V to the unit - LSU. If necessary, install a new CBF - harness;
switch micro, PL 4.15 Item 20.
• Check the wiring between the unit - LSU and the PBA main. Repair or install a new
CBF harness - LSU, PL 6.10 Item 2, as necessary.
• Install a new unit - LSU, PL 6.10 Item 1.
5. Refer to Wiring Diagram 1. Go to GP 1, Engine Test Mode Entry. Perform test number 5 to
check the MHV ADC and THV ADC read values. If necessary perform the following:
• Check the contact springs supplying the voltages to the ELA - OPC unit set and the
wiring to the SMPS + HVPS.
• Install a new ELA - OPC unit set, PL 9.10 Item 1.
• Install a new SMPS + HVPS, PL 1.10 Item 4.
6. Print a test pattern. For example, print the help list from the reports menu, GP 2 User
Entry Mode. If necessary, install a new PBA main, PL 1.10 Item 9.
Work Centre M20 Family

IQ2 Black Copies From the Scanner RAP

Use this RAP when the scanner produces black copies, but on-line printing is normal.
Procedure
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.
Refer to Wiring Diagram 1. Perform the following:
1. Go to GP 6 Maintenance, and perform the Adjust Shading procedure.
2. Check the ribbon cable between the ELA HOU - CCD module and the PBA main. If nec-
essary, install a new CBF signal - CCD FFC, PL 14.11 Item 17.
3. If necessary, install a new ELA HOU - CCD module, PL 14.11 Item 16.
4. If necessary, install a new PBA main, PL 1.10 Item 9.
March 2004
3-3
WARNING
Image Quality
IQ1, IQ2