CANON Error Code 120.370
HIGHCommon IssueFuser Unit Malfunction or Overheating (Canon 120.370)
Error 120.370 on Canon printers indicates a problem with the fuser unit, often related to its temperature regulation or internal components.
The Canon error code 120.370 signifies a critical issue within the printer's fuser assembly. The fuser is a vital component responsible for melting toner onto the paper using heat and pressure, permanently bonding the image. This error typically means the fuser is either not reaching its optimal operating temperature, is overheating, or has a sensor malfunction preventing it from reporting its status correctly. It's essentially a safety shutdown to prevent damage to the fuser itself or potential fire hazards. Common causes for this error include a worn-out fuser lamp, a faulty thermistor (temperature sensor), a damaged heating element, or issues with the fuser's power supply or control board. Less commonly, it could be triggered by a persistent paper jam that has stressed the fuser, or simply the fuser reaching the end of its operational lifespan. Because the fuser operates at very high temperatures, any deviation from its expected performance triggers this protective error code.
- 1
Turn off the printer completely and unplug it from the wall outlet. Wait for at least 15-20 minutes to allow the fuser to cool down completely.
- 2
Plug the printer back in and power it on. Observe if the error clears during the startup sequence.
- 3
Open all accessible covers and check for any visible paper jams, especially around the fuser area (usually located near the output tray). Carefully remove any jammed paper, ensuring no small pieces are left behind.
- 4
Inspect the fuser unit (if easily accessible and removable by the user, consult your printer manual). Look for any obvious damage, melted toner, or foreign objects.
- 5
Ensure the printer is connected directly to a wall outlet, not a surge protector or power strip, to rule out insufficient power supply.
- 6
Try updating the printer's firmware. Visit the Canon support website for your specific model and check for the latest firmware updates and installation instructions.
- 7
Perform a hard reset by unplugging the printer, holding down the power button for 30 seconds (even when unplugged), then plugging it back in and powering on.
If the error persists after trying all the DIY troubleshooting steps, especially after a cool-down period and paper jam checks, it's highly likely that the fuser unit itself or a related component (like the thermistor or control board) has failed. Fusers are considered consumable parts but require careful handling due to high temperatures and delicate components. Attempting to disassemble or repair the fuser without proper training can be dangerous and cause further damage. At this point, it's best to contact a certified Canon technician or a professional printer repair service for diagnosis and replacement.
Find a certified printer specialist near you →$250-$500 (for fuser unit replacement, parts and labor)
Actual costs may vary based on location and specialist
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