Troubleshooting For Fuser Unit Problems; Fuser Unit Failure; Troubleshooting For Led Assy Problems; Led Assy Failure - Brother HLL3290CDW Service Manual

4.8

Troubleshooting for Fuser Unit Problems

4.8.1

Fuser unit failure

Step
1
2
3
4
5
6
7
8
Note:
• Turn the power switch OFF and then ON again. Leave the machine for 15 minutes.
This problem may then be cleared.
• The machine may recover from the error, when the test printing of the maintenance mode
for service personnel is started. However, conducting this operation while the heater has
not yet cooled may cause the fuser unit to melt. Be careful.
4.9

Troubleshooting for LED ASSY Problems

4.9.1

LED ASSY failure

<User Check>
• Turn ON the power switch, then open the top cover and the back cover. Leave the machine
for a while to remove condensation.
Step
1
2
3
4
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8
Cause
Connection failure of the
center thermistor harness
Connection failure of the side
thermistor harness
Connection failure of the
heater harness
Connection failure of the eject
sensor harness
Eject sensor PCB failure
Low-voltage power supply
PCB failure
Fuser unit failure
Main PCB failure
Cause
LED ASSY attachment failure
Connection failure of the LED
ASSY flat cable
Connection failure of the LED
control flat cable
LED ASSY flat cable failure
LED control flat cable failure
LED control PCB failure
LED ASSY failure
Main PCB failure
Reconnect the center thermistor harness.
Reconnect the side thermistor harness.
Reconnect the heater harness.
Reconnect the eject sensor harness.
Replace the eject sensor PCB.
Replace the low-voltage power supply PCB.
Replace the fuser unit.
Replace the main PCB.
Reattach an LED ASSY.
Reconnect an LED ASSY flat cable.
Reconnect the LED control flat cable.
Replace an LED ASSY flat cable.
Replace the LED control flat cable.
Replace the LED control PCB.
Replace an LED ASSY.
Replace the main PCB.
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Remedy
Remedy
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