Brother FAX-2840 Service Manual page 73

Error code 75
Cooling Down
Wait for a while
The internal temperature thermistor detected a temperature higher than the specified value.
<User Check>
• Leave the machine for a while as the power remains ON.
Step
Internal temperature thermistor
1
failure
2 Main PCB failure
Error code 76
Print Unable 76
Turn the power off and then back on again.
The center thermistor of the fuser unit detected a temperature rise greater than the specified
value within the specified time.
Error code 78
Print Unable 78
Turn the power off and then back on again.
The center thermistor of the fuser unit detected a temperature fall greater than the specified
value within the specified time.
Step
1 Fuser unit failure
Low voltage power supply PCB
2
failure
3 Eject sensor PCB failure
4 Main PCB failure
Error code 7A
Print Unable 7A
Turn the power off and then back on again.
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 flat cable
2 Main motor failure
Low voltage power supply PCB
3
failure
4 Main PCB failure
Cause
Replace the internal temperature thermistor.
Replace the main PCB ASSY.
Cause
Replace the fuser unit.
Replace the low voltage power supply PCB
ASSY.
Replace the eject sensor PCB ASSY.
Replace the main PCB ASSY.
Cause
Reconnect the main motor flat cable.
Replace the main motor.
Replace the low voltage power supply PCB
ASSY.
Replace the main PCB ASSY.
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Remedy
Remedy
Remedy
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