Brother HL-6050 Service Manual page 232

M-4 Insufficient output from high-voltage power supply unit
Possible cause Step
High-voltage 1
contact
High-voltage 2
power supply
PCB
M-5 Fixing heater temperature failure
Possible cause Step
Poor thermistor 1
harness contact
Blown thermal 2
fuse
Thermistor 3
failure
Halogen heater 4
lamp failure
M-6 BD failure
Possible cause Step
Harness 1
connection
failure
Check
Do any of the terminals on the
high-voltage contacts have dirt
or contact burns?
Check the connections of the
connector between the high-
voltage power supply and the
engine PCB are secured
correctly.
Check
Is the contact of connector P6
on the engine PCB good?
Remove the fixing unit and
measure the resistance of the
thermal fuse. Is it open
circuit?
Is the thermistor installed
properly?
Remove the fixing unit and
measure the resistance of the
halogen heater lamp. Is it
open circuit?
Check
Is connector CN5 on the main
PCB secured correctly?
6-29
HL-6050/6050D/650DN SERVICE MANUAL
Result Remedy
Yes Clean the terminals.
Yes Replace the high-voltage
power supply PCB
No Reconnect the connector
between the high-voltage
power supply and the engine
PCB.
Result Remedy
No Reconnect the connector.
Yes Replace the fixing unit.
Yes Replace the fixing unit.
No Reinstall the thermistor
properly.
Yes Replace the halogen heater
lamp.
Result Remedy
No Reconnect the connector
securely.
Yes Replace the laser unit.