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Streaks, Fading and Repeating Marks: Reading Print Faults
Print faults are diagnosable from their pattern. Where the defect appears tells you which component is responsible, which usually saves replacing the wrong one.
Faded print across the whole page
Toner or ink running low, or a density setting turned down.
For laser: remove the cartridge, rock it gently side to side, refit. If the page improves, it was low toner. If not, check the density setting before buying anything.
For inkjet: run a nozzle check. Missing segments in the test pattern mean a partially blocked head, which a cleaning cycle may clear.
Fading down one side only
Usually toner unevenly distributed, or a cartridge not seated squarely. Remove it, rock it, refit, and make sure it clicks home on both sides.
If it persists after a fresh cartridge, the problem is in the machine rather than the supply.
Vertical streaks or lines
Down the length of the page, in the same place every time.
On a laser, this usually means debris on the drum or a worn drum wiper blade. On an inkjet, a blocked nozzle.
Distinguish white streaks from dark ones. A white line is something blocking transfer — nothing is being laid down. A dark line is excess toner or ink being deposited, which more often indicates a worn component.
Repeating marks at a fixed interval
The most diagnostic fault of all. A mark that repeats every few inches down the page corresponds to the circumference of a rotating part.
Measure the distance between repeats. Different components have different circumferences, and the printer’s service documentation usually lists them. On Brother lasers, a repeat of roughly 94 mm points to the drum unit; shorter repeats usually point to a developer roller.
This is why a repeating mark that survives a toner change is almost always the drum — and on Brother machines the drum is a separately replaceable part, so this is a cheaper fix than it first appears.
Toner that rubs off
A fusing problem. The toner has been placed correctly but not bonded to the paper by heat.
Causes: paper too heavy for the setting, damp paper, or a failing fuser. Check the media-type setting first — a printer told it is printing on plain paper will not apply enough heat for card.
Ghost images
A faint repeat of something printed earlier on the page. Usually a drum not fully clearing between rotations, associated with a worn drum or a very cold room.
Smearing along the direction of travel
On inkjet, usually the printhead striking wet ink — often caused by paper that is too thick for the head gap, or heavy coverage with fast drying settings.
On laser, dirty rollers in the paper path.
Colour cast or wrong colours
Run the printer’s calibration routine first. If one colour is missing entirely, check that cartridge specifically — on some printers a cartridge can be recognised as present while its nozzles are blocked.
Before replacing anything
- Print the printer’s own test page. If that is clean, the fault is in the file or the driver, not the hardware.
- Try a different paper from a fresh pack.
- Note whether the defect moves with the page or stays in the same position.
- Measure the repeat interval if there is one.
Those four steps identify the great majority of faults, and they cost nothing.
When it is the cartridge
If a fault appears immediately after fitting a new cartridge and disappears when the old one is refitted, the new cartridge is at fault. Our Return & Refund Policy covers defective items — contact us with the cartridge code and a photograph of the print fault.
