Xerox Phaser 790 User Manual

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Phaser 790/DocuColor 2006
IQ8
Initial Issue
Image Quality
IQ8 IOT Background RAP
Initial Actions
• Check the end-of-life counter (GP 3) for the Copy/Print Cartridge. If it is at or near end-of-
life, replace it (PL 5.1).
• Perform VisualCal (GP 16). If this does not resolve the problem, continue with this RAP.
Procedure
The problem is Single Color Background
YN
Remove the Copy/Print Cartridge. Examine the face of the ADC Sensor. The ADC Sen-
sor is clean.
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Go to the 009-340 RAP to troubleshoot the ADC Sensor Solenoid.
Examine the IBT Belt for excessive dirt, damage, or uncleaned toner. The IBT Belt is
clean.
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Go to the 009-704 Belt Cleaner RAP.
Remove the ROS (REP 9.3). Examine the ROS window. The ROS window is clean
and undamaged.
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Remove contaminants using a soft, dry, lint-free cloth. Use minimal pressure when
cleaning. If the window is scratched or damaged, replace the ROS (PL 5.1).
WARNING
HIGH VOLTAGE!
Exercise care when making the voltage check in the following steps.
Reinstall the ROS and the Copy/Print Cartridge. Remove the rear cover. Select Print
Configuration Page from the menu. Measure the voltage from the A terminal on the
HVPS to frame ground as the print is processing. The voltage cycles from 0 VDC to
roughly -500 VDC.
YN
Go to the 009-341 RAP to troubleshoot the BCR bias circuit.
Select Print Configuration Page from the menu. Measure the voltage from the C termi-
nal on the HVPS to frame ground as the print is processing. The voltage cycles from 0
VDC to roughly -500 VDC.
YN
Go to the 009-342 RAP to troubleshoot the Developer bias circuit.
Replace the IBT Belt (PL 7.2). If this does not resolve the problem, replace the Copy/Print
Cartridge (PL 5.1). If the problem persists, replace the MCU PWB (PL 11.2).
Check the following:
• Check the Developer Roll Spacing (ADJ 9.1) for the affected color.
• Check the end-of-life counter (GP 3) for the Dry Ink Cartridge. If it is at or near end-of-life,
replace it (PL 6.2).
• Access the IOT PARAM SET menu (See GP 3). Reset the toner density for the affected
color to the default value (3). Perform VisualCal.
• If the problem continues, examine the Developer Housing for the affected color. Check for
toner bridging, uneven brush, or loose High Voltage terminals. Clean, repair, or replace as
required (PL 6.2).

Xerox Phaser 790 Specifications

General

Brand	Xerox
Model	Phaser 790
Category	Copier
Language	English