Periodic Dirt; White Spots; Vertical White Banding; Options Service Check - Lexmark C920 Service Manual

5056-XXX

Periodic dirt

Possible cause
Oil coating fuser roller (OCR)
Photoconductor drum
Transfer belt unit

White spots

Possible cause
• LED printhead
• Photodeveloper
• Toner cartridge
Belt unit

Vertical white banding

Possible cause
• High voltage power supply

Options service check

Service Tip: When you have a problem with any of the options installed in the options slots on the interconnect
board, switch the non-operating option to one of the other option slots to isolate the failure.

Serial port

"Serial Wrap Test" on page
Run the
Note: The Serial Wrap Test is designed to check the serial port hardware by using a wrap plug, P/N 1329048,
and invoking the Serial Post Diagnostic Test. The test helps isolate the printer from the serial cable and host
computer. The test provides failure information on the display for approximately three seconds. If the test
indicates a problem, replace the RIP board.

Flash Memory Option(s)

Run a copy of the test page, and check to see if the option you are checking is listed. The printer does not
recognize the option being installed if the option is not listed. Be sure the memory card assembly is installed
correctly and is not broken or damaged. If the Memory card assembly is correctly installed, not broken or
damaged, then run the
problem continues, replace the RIP board.

DRAM Memory Option(s)

2-68
Service Manual
Action
Check for dirt or damage to the fuser rolls or the oil coating roller
(OCR).
Check for scratches on the surface, and replace if necessary.
Be sure the transfer belt is clean and not damaged. Replace parts as
necessary.
Action
Firmly install the photodeveloper and the toner cartridge into the printer.
Check the transfer belt unit for scratches or nicks. Be sure there is no
toner buildup on the belt. Replace the belt unit if it is damaged.
Action
Ensure that the cables are connected to the correct connectors on the
HVPS. See
3-12.
"Flash Test" on page 3-16. If the test fails, replace the Flash card assembly. If the
"High voltage power supply board" on page 5-14.