Brother HL-3450CN Service Manual page 319

CHAPTER 8 TROUBLESHOOTING
I-13 White Band
Phenomenon
White banding line appears in the horizontal direction, and consequently causes a missing
image as shown in print sample (13) of Page 8-45.
Main Causes
(1) Installation failure of the transfer unit, and deformation of the transfer roller.
(2) Contact failure of the transfer roller bias pole.
(3) TR cam clutch failure.
Countermeasures
(1) Confirm if the transfer unit is properly locked in position and that both ends of the transfer
unit are held by the hooks.
(2) Confirm if the transfer unit is properly installed or not.
(3) Replace the TR cam clutch with a new one. (See Section 4.1.7 of Chapter 7.)
(4) Replace the transfer unit with a new one. (See Section 4.6.1 of Chapter 7.)
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