Brother HL-1020, HL-820 manual Insufficient output from high-voltage power supply unit, BD failure

M-5

Insufficient output from high-voltage power supply unit

Possible cause	Step	Check	Result	Remedy
High-voltage	1	Do any of the terminals on the	Yes	Clean the high-voltage contact.
contact		high-voltage contacts have dirt
		or contact burns?
High-voltage	2	Check the connections of the	Yes	Replace the high-voltage
power supply		harness between the high-		power supply PCB.
PCB		voltage power supply and the
		panel sensor PCB are secured
		correctly.
			No	Reconnect the harness
				between the high-voltage
				power supply and the panel
				sensor PCB.

M-6

Fixing heater temperature failure

Possible cause	Step	Check	Result	Remedy
Poor thermistor	1	Are the connectors on the	No	Connect the connectors
harness contact		erase lamp PCB and the high-		securely.
		voltage power supply PCB
		secured correctly?
Blown thermal	2	Remove the fixing unit and	Yes	Replace the fixing unit.
fuse		measure the resistance
		between the input connectors.
		Is it open circuit?
Thermistor	3	Is the thermistor installed	Yes	Replace the fixing unit.
failure		properly?
			No	Reinstall the thermistor
				properly.
Halogen heater	4	Remove the fixing unit and	Yes	Replace the halogen heater
lamp failure		measure the resistance of the		lamp.
		fixing unit lamp. Is it open
		circuit?

M-7

BD failure

Possible cause	Step	Check	Result	Remedy
Harness	1	Is connector P2 on the panel	No	Connect it securely.
connection		sensor PCB secured correctly?
failure

IV-24