Lexmark 13P0150 - C 750dtn Color Laser Printer Service Manual page 90

Step Action and Questions
2
Toner Cartridge Check - Try a new toner cartridge for the
missing color.
Does a new toner cartridge fix the problem?
3
High Voltage Contact Block Assembly Check, PC Drum
Contact Pin - Check for a stuck PC Drum Contact in the HV
Contact Block Assembly for the missing color cartridge.
Refer to figure 1 for the location of the PC Drum Contact
Pin.
Is the pin stuck or does not operate smoothly?
4
High Voltage Contact Block Assembly Check, Continuity
Check for continuity from the PC Drum Contact Pin to the
PC Drum Developer Pin Spring.
Is there continuity?
5
High Voltage Contact Block Assembly Check, PC Drum
Developer Pin Spring - Check the PC Drum Developer Pin
Spring to make sure it is not bent or damaged.
Is the spring bent or damaged?
Colored lines, streaks, or smudges
Single color streaks in non-print areas are most likely caused by a cleaner problem in the
print cartridge. Replace the print cartridge.
A problem with all colors having spots or streaks that are different on each page is most
likely caused by damage to the ITU Assembly. Replace the
page
If only one color streaks in print areas, go to step 1.
Step Action and Questions
1
Print Cartridge Check - Try a new print cartridge.
Doe a new print cartridge fix the problem?
2
Printhead Check - The printhead lens may be contaminated
by toner. Check for any signs of contamination on the lens
of the printhead.
Is the printhead contaminated?
Evenly spaced horizontal marks or lines on the page
Black horizontal lines only are most likely caused by a shorted charge roll in the print
cartridge. Replace the black print cartridge.
If there are light horizontal lines in printed areas, go to
If there are Cyan, Magenta or Yellow horizontal lines, go to
2-70
Service Manual
4-40.
5060-XXX
Yes
Problem
Solved
Repair the HV
Contact Block
Assembly.
Go to Step 5
Replace the
PC Drum
Developer Pin
Spring.
Yes
Problem
Solved
Go to
"Printheads"
on page 4-33
and replace
the failing
printhead
No
Go to Step 3
Go to Step 4
Repair the HV
contact Block
Assembly.
Replace the
"HVPS
Developer
Board" on
page 4-36
"ITU Assembly" on
No
Go to Step 2
Replace the
"ITU
Assembly"
on page 4-40
"Step A" on page 2-71.
"Step B" on page 2-71.