Brother HL-820, HL-1020, HL-1040 manual Black spots, Pcb

I-15

Black spots

Possible cause	Step	Check	Result	Remedy
Drum unit	1	Are the spots at 94mm	Yes	If toner remains stuck, wipe it
		intervals?		off gently with a cotton swab.
		The problem is not solved after		Replace the drum unit if the
		printing a few pages.		OPC drum is scratched or
				deteriorated (exposed).
				(Refer to the following note.)
Fixing unit	2	Are the spots at 63mm	Yes	Check and clean the heat roller
		intervals?		with a cloth dampened with
		The problem is not solved after		alcohol.
		printing a few pages.		Replace the fixing unit.
High-voltage	3	Is the problem solved after the	Yes	Replace the high-voltage
power supply		high-voltage power supply		power supply PCB.
PCB		PCB is replaced?

Note: Clean the drum unit as follows:

(1)Place the printing samples in front of the process unit, and find the exact position of the image defect.

Position of smudge on the drum

94mm interval

Fig. 4-2

(2) Turn the drum gear by hand while looking at the surface of the OPC drum.

Fig. 4-3

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