Brother HL-2700CN Service Manual page 325

I-8 Vertical White Band
Phenomenon
White band appears in the vertical direction of printed image as shown in print sample
(8) of Fig.8-2.
Main Causes
1) Failure of the toner cartridge PU (blade).
2) Stain of the OPC charger roller PU.
3) Stain of the OPC belt.
4) Stain of the transfer belt.
Fig.8-7
Countermeasures
1) Replace the toner cartridge PU with a new toner cartridge PU.
2) Replace the belt cartridge PU with a new belt cartridge PU.
3) Replace the transfer unit PU with a new transfer unit PU.
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