Brother International HL 1850 Service Manual - Page 197

CHAPTER 6 TROUBLESHOOTING M-3 Main motor does not rotate Possible cause Failure of connector Main motor Engine PCB Main PCB Step 1 2 3 4 Check Is the connection of connector P9 on the engine PCB correct? Is the problem solved by replacing the main motor? Is the problem solved by replacing the engine PCB? Is the problem solved by replacing the main PCB? Result No Yes Yes Yes Remedy Reconnect the connector. Replace the main motor. Replace the engine PCB. Replace the main PCB. M-4 No paper supplied Possible cause Failure of connector Engine PCB circuit Paper pick-up clutch solenoid Separation pad / pick-up roller failure Main PCB Step 1 2 3 4 Check Is the contact of the solenoid connector on the engine PCB good? Set paper in the manual paper slot and make a test print by pressing the control panel button. Does the voltage between pins 2 (SOLENOID) and 1 (24V) of the P13 connector on the engine PCB change from approx. 24V DC to OV within the specified time? Is the surface of the separation pad or the pick-up roller dirty or worn out? Is the problem solved by replacing the main PCB? Result No Yes No Yes Yes Remedy Reconnect the connector. Replace the engine PCB. Replace the paper pick-up solenoid. 1) Clean the surface of the separation pad or pick-up roller. 2) Replace the separation pad or pick-up roller. Replace the main PCB. 6-30