Brother MFC640CW - 3 ] Communications Problems; 4 ] Paper;Document Feeding Problems

9-29 Confidential
[ 3 ] Communications problems
Problem Check:
(1) No tone is transmitted. • Main PCB
• MJ PCB
[ 4 ] Paper/document feeding problems
Problem Check:
(1) The "Enter Fax No." message
does not appear although
documents are set.
• Sensors by using maintenance-mode function code 32. (Refer
to Chapter 8, Section 8.4.7.)
• Document front sensor actuator
• Main PCB
(2) Document not fed. • ADF and its related sections
• ADF motor and its harness
• Document feed rollers and their related gears
• Main PCB
(3) Document double feeding • ADF parts
(4) Document jam • ADF motor
• Document rear sensor actuator
• Main PCB
(5) Recording paper not fed. • PF-related gears
• Main PCB
• Paper feed motor
• Paper tray
(6) Recording paper jam • Paper feeding mechanism
• Check that the carriage-head flat cable is connected to the
carriage PCB.