Diagnosis
Fingerprints and dust on the scanner glass (platen) of your Canon PIXMA MG3620 will cause visible defects, like smudges, spots, or hazy lines, to appear on every scanned image or photocopy. This is purely a surface contamination issue and does not indicate a scanner failure.
How to Fix It
To safely clean the scanner glass without causing damage or streaks, follow these steps:
- Turn the printer OFF using the power button and disconnect the power plug from the electrical outlet. This is a critical safety step.
- Fully open the document cover (the lid) and prop it up if possible to avoid it closing during cleaning.
- Use a completely dry, soft, and lint-free microfiber cloth, like one designed for camera lenses or eyeglasses. Gently smooth the cloth with your hand to ensure no trapped grit is present.
- Lightly wipe the glass in a single direction using straight, overlapping strokes. For stubborn fingerprints, you can breathe a light mist of moisture onto the cloth (never directly onto the glass) and then wipe gently, followed immediately by a dry pass with a clean portion of the cloth.
- Never use household glass cleaners, alcohol, ammonia, or abrasive pads, as they can strip anti-reflective coatings and cause permanent clouding or streaking.
If That Didn't Work
If smudges persist, double-check that the contamination is on the glass and not on the underside of the document cover or the white backing plate inside the lid, which can also be gently wiped with a dry cloth. For ingrained dirt, slightly dampen a cotton swab with distilled water (not tap water) and carefully clean the edge of the glass, avoiding the central scanning area. Ensure the glass is completely dry before powering the printer back on.
Heads Up
Always clean the glass with the printer unplugged to prevent accidental activation. Avoid excessive pressure, as the glass is mounted on a sensitive scanner carriage mechanism underneath. Regular cleaning with a dedicated microfiber cloth stored in a bag will prevent most dust buildup.