Brother MFC-8860DN - Page 385

Confidential
9-62
(F-5) Speaker is silent during on-hook dialing.
Possible cause
Step
Check
Result
Remedy
Connection
between main
PCB and speaker
1 Main PCB and speaker
are properly connected.
No Fix the connection properly.
Speaker 2 Replacement of speaker
solves the problem.
Yes Replace the speaker with a
normal part.
Connection
between main
PCB and NCU
PCB
3 Main PCB and NCU
PCB are properly
connected.
No Fix the connection properly.
Harness between
main PCB and
NCU PCB
4 Harness is damaged. Yes Replace the harness with a
normal part.
Connection
between main
PCB and control
panel PCB
5 Main PCB and control
panel PCB are properly
connected.
No Fix the connection properly.
Harness between
main PCB and
control panel PCB
6 Harness is damaged. Yes Replace the harness with a
normal part.
NCU PCB 7 Replacement of NCU
PCB solves the problem.
Yes Replace the NCU PCB with a
normal part.
Main PCB 8 Replacement of main
PCB solves the problem.
Yes Replace the main PCB with a
normal part.
(F-6) Dialing function does not switch between "tone" and "pulse".
Possible cause
Step
Check
Result
Remedy
Connection
between main
PCB and NCU
PCB
1 Main PCB and NCU
PCB are properly
connected.
No Fix the connection properly.
Harness between
main PCB and
NCU PCB
2 Harness is damaged. Yes Replace the harness with a
normal part.
NCU PCB 3 Replacement of NCU
PCB solves the
problem.
Yes Replace the NCU PCB with a
normal part.
Main PCB 4 Replacement of main
PCB solves the
problem.
Yes Replace the main PCB with a
normal part