What the makers say each defect means
These steps come from Brother, HP and Canon manuals for specific models. Menu names and settings differ between printers, so check the manual for yours.
Vertical lines or streaks
- Brother says to clean the corona wire inside the drum unit, then replace the toner, then the drum. It also warns that a corona wire tab left out of its home position leaves a vertical stripe.
- HP (Color LaserJet Pro MFP M277) says toner, paper and dust that build up inside the printer can cause streaks, lines and smears, and suggests a cleaning page. Its Print Quality Page shows whether streaks come from one toner cartridge, which HP says to replace, or from another part.
- Canon (imageCLASS) points to the paper, the toner and cleaning the fixing assembly from the printer’s menu.
Faint or light print
- Brother says to turn off Toner Save, clean the drum and corona wire, then replace the toner or drum.
- HP says to check the supplies status page and, if the whole page is too light, to turn off EconoMode in the driver.
- Canon says to check the paper, then the toner or drum, which may be near the end of its life.
Ghosting (a faint repeat of the image)
- Brother says to check the media type setting, then the drum.
- Canon lists replacing the toner, a Reduce Ghosting setting on some models, and cleaning the fixing assembly.
Smears, or toner that rubs off
- Brother says to check the media type setting and use its Improve Toner Fixing option.
- HP says to check that the paper type setting matches the paper, print a cleaning page, and use paper designed for laser printers, not paper made only for inkjets.
- Canon says to use suitable paper, check the toner and run Clean Fixing Assembly.
Gray background, spots or repeating marks
Print the blank page test to see these clearly. Canon has cleaning and special modes for a gray background on some models, and HP lists toner specks and repeating marks among the problems its cleaning page is for. Brother says spots that repeat at a fixed distance point to the drum. On its HL-L2400 series that distance is 94 mm (3.7 in), and it gives a drum dot check sheet to find the spot. Other models use other distances.
Colors that do not line up (color lasers)
- Brother (HL-L3210CW series) says to use its Color Registration function when solid areas of color or images have cyan, magenta or yellow fringes. It runs from the printer’s menu.
- Canon (imageCLASS LBP633Cdw) says a shift in the positions of the toner colors, which it calls print color mismatch, can make printouts look blurry, and corrects it with Correct Print Color Mismatch in the Adjustment/Maintenance menu.
- HP (Color LaserJet Pro MFP M277) says to calibrate the printer for misaligned color, colored shadows or blurry graphics, from Color Calibration in the Print Quality settings.
The registration targets on the CMYK test page and the center target on the alignment test page show colors that do not line up. Print one before and after to compare.
Built-in test pages on laser printers
- Brother: a Test Print and a Printer Settings report, from the printer’s menu.
- HP: the Color LaserJet Pro MFP M277 prints a Print Quality Page from its Reports menu, plus a supplies status page and a cleaning page.
- Canon: reports and lists from the menu, including a consumables status report on the imageCLASS MF753Cdw.
Laser or inkjet?
Laser printers have no ink nozzles or print head to clean or align, so the nozzle check does not apply. On the color lasers we checked, colors that do not line up have their own registration or calibration routine, described above. If you have an inkjet, use the inkjet printer test page. For a step-by-step diagnosis, see streaks or lines, smudges, faded print and blank pages.
Sources checked: Brother HL-L2400 series, improve the print quality, clean the corona wire, clean the drum unit, test print and printer settings, and HL-L3210CW series, color registration. HP, Color LaserJet Pro MFP M277 user guide (PDF), improve print quality section. Canon, imageCLASS MF269dw, MF753Cdw printing problems, cleaning the fixing assembly and reports and lists, and imageCLASS LBP633Cdw, correcting print color mismatch. Last checked 2026-10-06.



