Brother HL-5340D Service Manual page 84

FUSER UNITFAILURE
Step
Harness connection failure
1 between fuser unit connector and
eject sensor PCB ASSY
2 Fuser unit failure
Low-voltage power supply PCB
3
failure
4 Toner LED PCB failure
5 Main PCB failure
CAUTION :
This problem will be cleared if leaving the machine power ON for 15 minutes.
In the case of LED model, turn the power on while pressing the [Go] button, when the front
cover is open. And check that Back cover/Toner/Drum/Paper LEDs light up, and then
release the [Go] button. Check that all LEDs go off and press the [Go] button twice, and
then this problem may be cleared by that press the [Go] button once again after all LEDs
light up.
In the case of LCD model, turn the power on while pressing the [Go] button, when the front
cover is open. And check that "USERS MODE" is displayed on the LCD, and then release
the [Go] button. Check that Data LED go off and press the [Go] button twice, and then this
problem may be cleared by that press the [Go] button once again after "USERS MODE" is
displayed on the LCD in the state that the backlight lights up.
This operation will melt the fuser unit if the heater is hot. It is necessary to leave for 15
minutes.
LASER UNIT FAILURE
Laser diode failure/Polygon motor failure
Step
Laser unit harness connection
1
failure
FG harness ASSY connection
2 failure
3 Laser unit failure
4 Main PCB failure
MAIN MOTOR FAILURE
Step
Main motor harness connection
1
failure
Motor load
2
3 Main motor failure
Low-voltage power supply PCB
4
failure
5 Main PCB failure
Cause
Check the harness connection between
fuser unit connector and eject sensor PCB
ASSY.
Replace fuser unit.
Replace the PS PCB unit.
Replace the toner LED PCB ASSY.
Replace the main PCB ASSY.
Cause
Check the two harness connections of the
laser unit and reconnect them.
Check the FG harness ASSY connection
between the laser unit and main PCB
ASSY. Then reconnect it.
Replace the laser unit.
Replace the main PCB ASSY.
Cause
Check the harness connection of the main
motor and reconnect it.
Remove the motor load cause to turn the
each gears.
Replace the drive sub ASSY.
Replace the PS PCB unit.
Replace the main PCB ASSY.
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Remedy
Remedy
Remedy
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