DIAGNOSIS That's the sound of the fuser unit's gears stripping or a foreign object jammed in the paper path near the fuser.
FIX Immediately power off and unplug the printer. Inspect and clear the fuser area.
- Open the rear cover (back of the printer).
- Look for any torn paper, bits of label, or debris lodged in the green fuser assembly rollers or the gears on its side.
- Carefully remove any debris. Gently rotate any gears by hand to check for smooth movement.
- Close the cover and test.
IF THAT DIDN'T WORK The fuser drive gear itself is likely cracked. This is a known wear part. You'll need to replace the entire fuser unit (Canon part FM4-8584).
HEADS UP Never use label sheets, transparencies, or wrinkled paper not rated for laser printers. They melt and shred inside the hot fuser, causing this exact damage.