Brother MFC-8460N Servise Manual page 381

(L-2) The control panel does not work.
User Check
(1) No
Possible cause
Key sticking
Connection
between main
PCB and control
panel PCB
Harness between
main PCB and
control panel
PCB
Rubber key
Control panel
PCB
Main PCB
(L-3) Printing from Macintosh applications fails.
User Check
(1) Verify that the printer driver supplied with the machine has been installed in the system
folder and selected in the selector.
(2) Check the port selected in the selector. The selected port has to match the actual port to
which the machine cable is connected.
Possible cause
Fault in machine
Breakage of main
PCB
Step Check
1 Any key on control
panel is stuck.
2 Main PCB and
control panel PCB
are properly
connected.
3 Harness is damaged.
4 Replacement of
rubber key solves the
problem
5 Replacement of
control panel PCB
solves the problem.
6 Replacement of main
PCB solves the
problem.
Step Check
1 Test page can be
printed using the
method described in
8.4.5 'Test Pattern 1'
in Chapter 8.
2 Printing can be made
using an appropriate
PC, machine cable,
and RS-100M?
Result
Yes Clean up the panel cover, or
remove the burrs from panel
cover and panel keys.
No Fix the connection properly.
Yes Replace the harness with a normal
part.
Yes Replace the rubber key with a
normal part.
Yes Replace the control panel PCB
with a normal part.
Yes Replace the main PCB with a
normal part.
Result
No Check the symptom of the
problem and refer to an
appropriate section in this
Chapter to solve the problem.
No Replace the main PCB.
9-57
Remedy
Remedy
Confidential