Canon Pixma Printer F21 Error Code Guide (Fast Fix)

Canon’s official playbook for this kind of fault is simple: reset power, clear jams, reseat parts, then send it in if the error sticks. Do this in order:

• Hard power reset
  • Turn the printer off with the Power button.
  • Unplug the power cord from the wall for at least 60 seconds.
  • While it is unplugged, press and hold the Power button for 10 to 15 seconds to bleed off any leftover charge.
  • Plug it back in and power it on. See if F21 clears.
• Check for paper scraps and carriage obstruction
  • Open the main top cover or front cover where you normally access the ink.
  • Look along the entire paper path with a flashlight: input tray, feed rollers, and the exit path.
  • Pull out any torn paper, labels, or foreign objects. Go slow so you do not rip more paper deeper into the mechanism.
  • With power off, gently slide the print head carriage left and right. It should move smoothly; if it binds or hits something solid, you still have a jam or a bent part.
• Reseat cartridges and, if removable, the print head
  • With the cover open and power on, let the carriage move to the cartridge change position, then turn the power off.
  • Remove every ink cartridge and check for obvious leaks or broken plastic.
  • If your model has a removable print head, unlatch it and lift it out carefully. Check for wet ink around the contacts or burnt spots.
  • Wipe the gold contacts on the print head and inside the carriage with a slightly damp, lint free cloth or coffee filter. No alcohol, no soaking.
  • Reinstall the print head firmly, then the cartridges, making sure each one clicks into place.
  • Power back on and test. A poor connection here is a common trigger for hardware fault codes.
• Inspect the encoder strip and belt
  • Behind the carriage you will see a thin, clear plastic strip running left to right. That is the encoder strip; the carriage uses it to know its position.
  • If it is greasy, smeared with ink, or popped out of its slots, the logic board can throw a generic fault like F21.
  • Do not yank it. If it is dirty, very gently wipe it with a barely damp, lint free cloth from one side to the other.
  • Look at the black rubber belt that drives the carriage. If it is shredded, loose, or missing teeth, the printer will usually need professional repair.
• Run a test after each change
  • After any of the steps above, close all covers, turn the printer back on, and see if F21 returns.
  • If it lets you into the menu, run a nozzle check or test print. If that fails with grinding noises or stalls, the internal mechanics are still not right.

If F21 is still showing after all of this, Canon’s official next step is a service visit. That usually means main board or print head diagnostics with service tools the average user does not have.