prints have faint streaks and smudges down the page, cleaned the drum but it didn't help.

Diagnosis

The presence of vertical streaks and smudges that persist after cleaning the drum indicates that the issue is occurring during the final stages of the printing process—specifically during the transfer or fusing phase. While the drum (OPC) creates the image, the transfer roller pushes that image onto the paper, and the fuser unit melts the toner into the fibers. If you see repetitive smudges (ghosting) or streaks that appear at regular intervals down the page, the culprit is usually a build-up of waste toner or a physical tear in the fuser's pressure roller. To confirm the source, perform a "half-way" test: start a print job and open the front cover or pull the power plug as soon as the paper reaches the fuser but before it exits the machine. If the streaks are already present on the paper before it passes through the fuser rollers, the issue lies with the transfer roller or the corona wire. If the page looks clean until it hits the fuser, the fuser film is torn or coated in leaked toner, which "drags" the image across the page.

How to Fix It

Since you have already addressed the drum, follow these precise steps to clear the transfer path and the charging system:

1. Power down the MF269dw II and unplug the power cable to avoid electrical discharge from the high-voltage components.
2. Open the front cover and remove the toner cartridge/drum assembly entirely to expose the interior cavity.
3. Locate the green spongy transfer roller positioned on the underside of the printer chassis. Using a dry, lint-free microfiber cloth, gently wipe the roller from left to right. Do not apply heavy pressure, as compressing the foam can cause uneven density in your prints.
4. Locate the corona wire cleaner—this is the small plastic slider (usually green or blue) attached to the drum unit or the internal housing. Slide it firmly from one end to the other three times. This clears the ionized dust that causes vertical white or black streaks.
5. Inspect the fuser exit rollers (the rubber rollers at the very back where the paper exits). Use a can of compressed air to blow out any loose toner clumps trapped in the rollers.
6. Reinstall the cartridge, close the cover, and run a "Status Page" from the printer menu to check for clarity.

If That Didn't Work

• Replace the Fuser Unit: If you see a repeating smudge every 3-4 inches, the heat-shrink film on the fuser roller is likely punctured. This cannot be cleaned; the entire fuser assembly must be replaced. Look for a part number corresponding to the MF260 series fuser.
• Check Paper Settings: If you are using heavy cardstock or labels, the fuser may not be reaching the correct temperature, causing "cold offset" smudging. Go to Menu > Paper Settings > Type and ensure it is set to "Heavy" or "Bond" rather than "Plain."
• Swap the Toner Cartridge: A leaking developer unit inside the Canon 052/054 cartridge can spill excess toner onto the transfer roller faster than the printer can clean it. Replace the cartridge with a known-good unit to see if the streaks vanish.
• Deep Clean the Pickup Rollers: Sometimes streaks are actually "scuff marks" caused by misaligned paper. Clean the rubber pickup and separation rollers with a damp (not dripping) cloth and distilled water to ensure the paper is entering the fuser perfectly square.

Heads Up

• Avoid Chemical Solvers: Never use rubbing alcohol, acetone, or glass cleaner on the green transfer roller or the drum; these chemicals dissolve the conductive coatings and will permanently ruin the image quality.
• Corona Wire Caution: Never touch the silver corona wire with your bare fingers. The oils from your skin create "blind spots" that result in permanent white streaks on every page.
• Toner Management: Always shake the toner cartridge horizontally 5-6 times before installation to prevent "clumping," which can lead to erratic toner distribution and smudging.
• Environmental Control: High humidity can cause toner to clump on the transfer roller. If the printer is in a basement or garage, consider a dehumidifier to prevent "damp" smudging.