scanner glass gets dirty so fast and leaves streaks on every scan, how do i clean it properly?

Diagnosis

The streaks appearing on your HP OfficeJet Pro 8135e scans are typically caused by a combination of "platen grime" and residue on the underside of the scanner lid. Because this model uses a CIS (Contact Image Sensor) array, even a microscopic speck of dust, a fingerprint oil smudge, or a tiny piece of adhesive residue from a label can obstruct the light path, resulting in a solid vertical or horizontal line across the entire digitized image. The problem is often compounded by the white plastic backing on the underside of the lid. When this backing becomes dirty or frayed, it allows external light to leak into the scan area or transfers debris back onto the glass every time the lid is closed. If you see a consistent line in the same spot on every page, the contaminant is on the glass; if the streaks are faint and intermittent, the issue is likely the lid backing or a misalignment of the scan head.

How to Fix It

To achieve a professional, streak-free scan on the 8135e, follow this precise decontamination process:

1. Power down the printer and unplug the power cable from the wall to prevent any electrical surge or accidental movement of the scan carriage during cleaning.
2. Lift the scanner lid completely. Use a high-density microfiber cloth (avoid paper towels as they leave lint and can scratch the glass).
3. Apply a small amount of 70% Isopropyl Alcohol or a streak-free glass cleaner directly to the cloth, never directly onto the glass. Applying liquid to the glass can allow fluid to seep into the edges of the platen, potentially damaging the sensor array.
4. Wipe the glass using a "S-pattern" or single-direction strokes from one side to the other. Avoid circular motions, as this simply redistributes the oils and dust rather than removing them.
5. Pay special attention to the very edges of the glass where the frame meets the platen; dust often collects in these crevices and migrates to the center during the scan process.
6. Flip the scanner lid over and wipe the white underside backing with a dry microfiber cloth. If there are ink stains on the white plastic, use a damp cloth with a drop of mild dish soap, then dry it immediately.
7. Use a dry, clean section of the microfiber cloth to buff the glass until no haze remains.

If That Didn't Work

• Check the ADF Glass Strip: If the streaks only appear when using the Automatic Document Feeder (ADF) and not the flatbed, the culprit is the small, narrow strip of glass to the left of the main platen. Clean this narrow strip with a cotton swab dipped in isopropyl alcohol, ensuring you remove any tiny dots of ink or correction fluid that may be stuck to the surface.
• Inspect for Micro-Scratches: Hold a bright flashlight at a low angle across the glass. If you see physical scratches (permanent grooves), cleaning will not work. You will need to replace the platen glass assembly, as the sensor reads these scratches as black lines.
• Reset the Calibration: In some cases, "streaks" are digital artifacts. Power cycle the printer while the scanner lid is open, then close it and run a "Clean Pages" or "Calibration" cycle from the HP Smart app settings to ensure the sensor is properly zeroed.
• Deep Clean the Edge Bezel: Use a can of compressed air to blow out the gap between the glass and the plastic housing. Often, a clump of dust sits on the bezel and drops onto the glass every time you close the lid, causing recurring streaks.

Heads Up

• Never use acetone, nail polish remover, or abrasive scouring pads on the scanner glass; these will permanently strip the anti-reflective coating and blur your scans.
• Always ensure the white underside of the lid is completely dry before closing it, as moisture can trap humidity against the glass, leading to fogging or streaks in high-humidity environments.
• If you frequently scan documents with staples or paperclips, consider placing a clean sheet of white cardstock on the lid backing to act as a sacrificial barrier against grime.
• Avoid using "heavy-duty" industrial cleaners; the plastics surrounding the HP 8135e glass are susceptible to chemical stress cracking if exposed to harsh solvents.