Troubleshooting Image Defects - Brother HL-1660e Series User Manual

3.2 Troubleshooting Image Defects

Light
I-1
Possible cause Step
Toner shortage
1
ECONOMY
2
mode
Printing 3
density setting
4
-
Paper failure
5
Transfer roller
6
failure
7
Transfer input
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
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 cartridge.
Open the drum shutter of the EP-ED 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 scanner
unit is improved?
Result
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Yes
Yes
VI - 4
Remedy
Replace EP-ED cartridge.
Cancel the ECONOMY
mode.
Adjust the proper setting
on the control panel.
Go to the Step 9.
Use recommended paper.
Clean the transfer roller [Use
dry lint-free paper (producing
little paper dust) to clean the
transfer roller. Never use
solvents] and, if dirts subsist,
replace the transfer roller assy.
Replace the main PCB assy
or the harness.
Clean the contact to assure
the continuity.
Replace the high-voltage
power supply assy.
Replace the scanner unit or
the harness.