Brother HL-3170CDW - Manual (Page 155)

Routine Maintenance
149
4
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