Diagnosis
The "Out of Paper" error on the Canon PIXMA TS6420a occurs when the printer's optical or mechanical paper detection system fails to confirm the presence of a sheet during the pickup cycle. This is rarely a complete hardware failure and is typically caused by a misalignment of the paper stack or a failure of the pickup rollers to create enough friction to move the paper forward, which the printer interprets as an empty tray. Specifically, the TS6420a uses a top-loading rear tray where the paper must be seated precisely against the right-hand side of the guide. If the paper is leaning at an angle or is slightly curled, the rollers may spin without grabbing the page. Additionally, the small plastic sensor lever inside the feed slot can become stuck in the "up" position due to dust buildup or a small scrap of torn paper from a previous jam, tricking the logic board into thinking the tray is vacant even when full.
How to Fix It
Follow these precise steps to reset the paper feed mechanism and clear the sensor error:
- Power down the printer completely and unplug the power cable from the wall to discharge any static in the sensor board.
- Remove the entire stack of paper from the rear tray. Inspect the tray for any small debris, such as staples, paper clips, or tiny torn fragments of paper that may be obstructing the feed path.
- Take the stack of paper and "fan" the edges thoroughly. This breaks the static cling and prevents multiple sheets from being pulled at once, which often triggers a false "out of paper" reading.
- Check the paper for curling. If the sheets are curled away from the rollers, gently bend them back to ensure a flat surface.
- Insert the paper back into the tray, ensuring the stack is pushed firmly against the right-side guide.
- Adjust the plastic paper guide (the blue or grey slider) so it is snug against the edge of the paper, but not so tight that it bows the paper. If the guide is too loose, the paper will shift, causing the sensor to lose track of the stack.
- Ensure the paper is not loaded beyond the maximum fill line indicated on the tray wall. Overloading puts too much pressure on the pickup rollers, preventing them from rotating.
- Plug the printer back in and power it on. When the "Out of Paper" message appears on the OLED screen, press the "OK" button to force a re-scan of the tray.
If That Didn't Work
- Clean the Pickup Rollers: The rubber rollers may have accumulated "paper dust" or oils, making them slippery. Dampen a lint-free cloth with distilled water (do not use alcohol) and gently wipe the rubber rollers located at the base of the rear tray. Rotate the rollers manually to clean the entire circumference.
- Hard Reset the Logic Board: While the printer is on, unplug the power cord from the back of the unit. Wait exactly 60 seconds. While unplugged, hold the power button for 15 seconds to drain the capacitors. Plug it back in and restart.
- Check for "Ghost" Jams: Open the scanning unit (the top cover) and check for any tiny scraps of paper lodged near the carriage path. Even a piece the size of a fingernail can trip the sensor and trigger an "out of paper" or "paper jam" error.
- Test with Different Paper Weight: If you are using heavy cardstock or photo paper, the printer may struggle to grip the sheet. Try loading a few sheets of standard 20lb multipurpose office paper. If the standard paper works, the issue is the friction coefficient of your specialty paper.
Heads Up
- Avoid using "economy" or ultra-thin paper (below 60 gsm), as these often slide through the rollers without triggering the sensor, leading to persistent "Out of Paper" errors.
- Never use a vacuum cleaner inside the paper tray; the static electricity generated by the nozzle can damage the sensitive optical sensors of the TS6420a.
- Always store your paper in a cool, dry place. High humidity causes paper to dampen and swell, which increases the likelihood of the rollers slipping.
- If you notice the rollers are visibly worn or have "flat spots," you will need to replace the pickup roller assembly, as cleaning will no longer provide the necessary grip.