Brother Facsimile Equipment MFC7420 - Manual (Page 246)

Confidential 9 -5 8
F-3 FAX can't be received.
User Check
(1) Verify that the telephone cord is securely inserted.
Possible cause Step Check Result Remedy
Receive mode
setting 1 Receive mode is set to
automatic receive mode. No Set the receive mode to
automatic receive mode.
NCU PCB 2 Replacement of NCU
PCB solves the problem. Yes Replace the NCU PCB with a
normal part.
Main PCB 3 Replacement of main
PCB solves the problem. Yes Replace the main PCB with a
normal part.
F-4 No bell ring.
Possible cause Step Check Result Remedy
Ring delay 1 Ring delay is set to "0". Yes Set the ring delay to other than
"0".
Ring volume 2 Ring volume is set to
"OFF". Yes Set the ring volume to other
than "OFF".
Harness between
main PCB and
scanner unit 3 Harness is damaged. Yes Replace the harness with a
normal part.
Connection
between main
PCB and NCU
PCB 4 Main PCB and NCU
PCB are properly
connected. No Fix the connection properly.
Harness between
main PCB and
NCU PCB 5 Harness is damaged. Yes Replace the harness with a
normal part.
Speaker 6 Replacement of speaker
solves the problem. Yes Replace the speaker 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.