Brother HL-L3230CDW Wireless Compact Printer - Manual (Page 298)

5. Open the top cover until it locks in the open position.
WARNING
HOT SURFACE
The machine's internal parts will be extremely hot. Wait for the machine to cool down before touching
them.
6. The color of printed dots on the Drum Dot Check Sheet is the color of the drum you should clean. Remove
the toner cartridge and drum unit assembly that matches the color causing the problem.
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