Brother HL-1260 Service Manual page 83

Completely blank
I-3
Possible cause Step
EP-ED cartridge 1
Development 2
input signal
error
Failure in power 3
supply terminal
4
LD failure
Failure in
development
high-voltage circuit
All black
I-4
Possible cause Step
Beam detection
1
error
Does printed image improve when the EP-ED
EP-ED cartridge 2
cartridge is replaced?
Do the pins 1 and 2 of the connector P6 on the
Charging input 3
main PCB have the following value respectively
signal error
when a sheet of paper is fed from the MP tray?
P6-1 pin (HV1AC) --- Change in voltage from 6V
approx. to 0V just when a sheet of paper is fed.
P6-2 pin (HV1DC) --- Change in voltage from 9V
approx. to 0V just when a sheet of paper is fed.
Is there any dirt on the cartridge side charging
4
Dirt on power
terminal of the transfer unit and on the terminal of
supply terminal
the high-voltage power supply charging unit?
Failure in the
(is there continuity between them?)
charging high-
voltage circuit
LD failure
Check
Does printed image improve when the EP-ED
cartridge is replaced?
Do the pins 3, 4 and 5 of the connector?
P6 on the main PCB have the following value
respectively when a sheet of paper is fed from
the MP tray?
P6-3 pin (DBAC) --- Change in voltage from
6V approx. to 0V just when a sheet of paper is
fed from the registration unit.
P6-4 pin (DBDC) --- Change in voltage from
9V approx. to 0V just when a sheet of paper is
fed from the registration unit.
P6-5 pin (DNSTY) --- Change in voltage to
2.5V just when a sheet of paper is fed.
Is there any dirt on the cartridge side
development terminal of the transfer unit and
on the terminal of the high-voltage power
supply development unit? (is there continuity
between them?)
Does print quality improve when the scanner
unit is improved?
Check
Is the printer hung up with the PRINT message
remaining on the display even after a printing
when only a copy is printed?
Result
Yes
No
No
Yes
No
Result
Yes
Yes
No
No
Yes
VI - 6
Remedy
Replace the EP-ED cartridge.
Replace the main PCB assy
or the harness.
Clean the terminal to assure
the continuity.
Replace the scanner unit or
the harness.
Replace the high-voltage
power supply PCB assy.
Remedy
Replace the scanner unit or
the harness.
Replace the EP-ED cartridge.
Replace the main PCB assy
or the harness.
Clean the contact to assure
the continuity
Replace the high-voltage
power supply PCB assy and,
if the problem is not resolved,
replace the scanner unit or
the harness.