Brother HL-5440D Service Manual page 75

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