Canon imageRUNNER ADVANCE DX C3835i Faq Manual page 19

If the DADF-BA is attached:
1.
Open the feeder, and clean the lower side
document feed scanning area using the
supplied glass-cleaning sheet.
N O T E
Do not use glass cleaner or an alcohol solution,
etc., as they will strip away the stain-proof
coating.
2.
Close the feeder.
N O T E
If black streaks still appear after dirt removal,
perform the following procedure to execute [Clean
Feeder].
User's Guide
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