Brother HL-3140CW User Manual page 154

Routine Maintenance
g
Push down the green lock lever and take the toner cartridge out of the drum unit.
h
Turn the drum unit as shown in the illustration. Make sure that the drum unit gear (1) is on the left side.
i
Read following information from the drum dot check sheet.
 Dot location: The sheet has eight numbered columns. The number of the column with the printed dot
in it is used to find the dot position on the drum.
1
4
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