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Confidential
1-50
Faint print
User Check
- Check that the machine is installed on a level surface.
- Replace the toner cartridge with a new one.
- Clean the scanner windows with a soft cloth.
Step
Cause
Check
Result
Remedy
1
Laser unit failure
Is the problem solved
after replacing the laser
unit?
Yes
Replace the laser unit.
2 Toner
empty
sensor failure
Is the “Toner Life End”
message indicated on the
LCD after replacing the
current toner cartridge
with an empty one?
No
Replace the toner sensor
PCB ASSY (TE/NEW) of
the appropriate color.
White spots on one color image
User Check
- Toner may be empty. Replace the toner cartridge with a new one.
- If the same problem occurs after printing a few pages, the adhesive of the label or the like,
paper powder or dirt may be attached on the surface of the exposure drum.
When the size of the white spots is less than 0.35mm, feed the drum cleaning sheet from the
MP tray one to three times to clean the drum.
(For the procedure, refer to
“Drum Unit Cleaning Mode”
in Chapter 5.)
When the size of the spots is 0.35mm or more, or when the same problem occurs after
feeding the drum cleaning sheet, wipe off the dirt on the exposure drum with a cotton swab.
(For the procedure, refer to
Note in the next pages
.)
- The drum unit may be damaged. Replace the drum unit with a new one.
Step
Cause
Check
Result
Remedy
1
Drum unit failure
Are the white spots at
75.0 mm (exposure drum
circumference) intervals?
Yes
If the exposure drum
surface is scratched,
replace the drum unit.
2 Drum
unit
connection failure
Are the electrodes on the
drum unit and machine
body dirty?
Yes
Clean both electrodes.
3 Transfer
HVPS
PCB failure
Is the problem solved
after replacing the
transfer HVPS PCB
ASSY?
Yes
Replace the transfer
HVPS PCB ASSY.
4 Charge
HVPS
PCB failure
Is the problem solved
after replacing the charge
HVPS PCB ASSY?
Yes
Replace the charge
HVPS PCB ASSY.
Summary of Contents for HL-4040CN
Page 265: ...Confidential 4 7 11 Alert warning message of WHQL appears Click Continue Anyway to proceed ...
Page 320: ...Confidential 6 12 Charge High voltage Power Supply PCB Circuit Diagram 1 4 ...
Page 321: ...Confidential 6 13 Charge High voltage Power Supply PCB Circuit Diagram 2 4 ...
Page 322: ...Confidential 6 14 Charge High voltage Power Supply PCB Circuit Diagram 3 4 ...
Page 323: ...Confidential 6 15 Charge High voltage Power Supply PCB Circuit Diagram 4 4 ...
Page 324: ...Confidential 6 16 Transfer High voltage Power Supply PCB Circuit Diagram 1 2 ...
Page 325: ...Confidential 6 17 Transfer High voltage Power Supply PCB Circuit Diagram 2 2 ...
Page 326: ...Confidential 6 18 Low voltage Power Supply PCB Circuit Diagram 100V ...
Page 327: ...Confidential 6 19 Low voltage Power Supply PCB Circuit Diagram 200V ...