Troubleshooting Image Defects - Brother HL 2060 - B/W Laser Printer Service Manual

3.2

Troubleshooting Image Defects

I-1 Light
Possible cause Step
Toner shortage 1
ECONOMY 2
mode
Printing 3
density setting
4
Paper failure 5
Transfer roller 6
failure
Transfer input 7
signal error
Dirt on power 8
supply terminal
Failure in the
transfer high-
voltage circuit
Insufficient LD 9
light
Continued to the following page
Check
Does printed image improve when the
EP-ED HC cartridge is replaced?
Is the ECONOMY mode active?
Does printed image improve when printed
density setting is changed on the control
panel?
During a printing, open the toner cartridge lid
in the printer and pull out the EP-ED HC
cartridge.
Open the drum shutter of the EP-ED HC
cartridge and check the toner image on the
drum.
Is the toner image before transfer is light?
Does the print quality improve when fresh
paper is used?
Does the print quality improve when print is
made with transfer roller changed?
Do the pins 7 and 8 of the connector P6 on the
main PCB have the following value
respectively when a sheet of paper is fed from
the MP tray?
P6-7 pin (HVT2) --- Change in voltage from
15V approx. to 0V about 1 second after paper
feeding.
P6-8 pin (HVT3) --- Change in voltage from 9V
approx. to 0V just when the voltage at the 7
pin changes from 0V to 15V.
Clean the transfer roller right end bearing, the
check continuity between the transfer roller
power supply spring and the terminal
of the high-voltage transfer unit.
Is there continuity?
Does print quality improve when the laser unit
is improved?
VI-4
Result Remedy
Yes Replace EP-ED HC
cartridge.
Yes Cancel the ECONOMY
mode.
Yes Adjust the proper setting
on the control panel.
Yes Go to the Step 9.
Yes Use recommended paper.
Yes Clean the transfer roller
[Use dry lint-free paper
(producing little paper
dust) to clean the
transfer roller. Never use
solvents] and, if dirt
subsists, replace the
transfer roller assy.
No Replace the main PCB
assy or the harness.
No Clean the contact to
assure the continuity.
Yes Replace the high-voltage
power supply assy.
Yes Replace the laser unit or
the harness.