Brother HL-L3230CDW Wireless Compact Printer - Manual (Page 294)

7. 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.
CAUTION
We recommend placing the toner cartridge and drum unit assemblies on a clean, flat surface with
disposable paper underneath it in case you accidentally spill or scatter toner.
IMPORTANT
To prevent damage to the machine from static electricity, DO NOT touch the electrodes shown in the
illustration.
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