Brother HL-5450DN - Page 75

2-39
Confidential
 Error code 7600
The center thermistor of the fuser unit detected a temperature rise greater than the specified
value within the specified time.
Error code 7800
The center thermistor of the fuser unit detected a temperature fall greater than the specified
value within the specified time.
 Error code 7A00
Cannot detect the synchronized signal of the main motor. The speed of the main motor does
not stabilize within the specified time.
Fuser Error / Print Unable 76
Fuser Error / Print Unable 78
<User Check>
• Turn OFF the power switch. After several seconds, turn ON the power again and check
that this error is reset.
Step Cause Remedy
1
Connection failure of the center
or side thermistor harness of
the fuser unit
Check the connection of the center or side
thermistor harness of the fuser unit, and
reconnect it if necessary.
2
Connection failure of the heater
harness of the fuser unit
Check the connection of the heater harness of
the fuser unit, and reconnect it if necessary.
3
Connection failure of the eject
sensor PCB harness
Check the connection of the eject sensor PCB
harness, and reconnect it if necessary.
4
Connection failure of the low-
voltage power supply PCB
harness
Check the connection of the low-voltage power
supply PCB harness, and reconnect it if
necessary.
5
Eject sensor PCB failure Refer to "1.3.8 Check sensor operation
(function code: 32)" in Chapter 5 to check the
sensor operation. If the sensor operation is
faulty, replace the eject sensor PCB ASSY.
6
Low-voltage power supply PCB
failure
Replace the low-voltage power supply PCB
ASSY.
7 Main PCB failure Replace the main PCB ASSY.
Print Unable 7A
Step Cause Remedy
1
Connection failure of the main
motor harness
Check the connection of the main motor
harness, and reconnect it if necessary.
2 Main motor failure Replace the main motor ASSY.
3 Main PCB failure Replace the main PCB ASSY.