Brother MFC-8460N Servise Manual page 330

<The solution when Error Code
The heater may be overheating when these kinds of error occur. Therefore, the heater is
programmed to turn off the power for 10 minutes after the switch is on for the safety concern when
the error occurs.
To help the heater work properly, it's necessary to follow the operating procedures as below after
taking measures against the cause of the error.
1. Turn off the switch. Wait until the temperature of the heater lowers enough.
2. Turn on the switch.
3. Either display the maintenance mode then returns to the initial original maintenance mode, or
keep the power on for 10 minutes under inspection.
Error Code
(Hex)
7A Main motor does not
synchronize with the reference
clock.
7B ASIC error on the main PCB.
(Not used.)
7C Not used.
7D Dust on the drum.
7E, 7F Not used.
80 At the start of FAX message
printing, the controller detects
that paper is smaller than A4
size in width.
81 Recording paper jam.
(Not used.)
82 Recording paper jam in paper
pull-in operation. (Not used.)
83 Recording paper jam.
(The registration sensor comes
ON too early in the paper
feeding operation.)
76, 77, 78 shown in the machine>
Symptom
9-6
Probable Cause
Main PCB defective
Main motor defective
Corona wire is dirty.
Paper smaller than the
specified size loaded in
the paper tray
Main PCB defective
Paper is not correctly
set in the paper tray
Separation pad
damaged
Registration sensor
actuator unhooked
Main PCB defective
Solution
Replace the main PCB.
Replace the main motor.
Cleaning the corona wire.
Load the correct size of
paper.
Replace the main PCB.
Reload paper.
Replace the paper tray.
Set the registration sensor
actuator into place.
Replace the main PCB.
Confidential