E804-0001imagePRESS C165

Canon imagePRESS C165 Error E804 Troubleshooting

The E804 code on the Canon imagePRESS C165 indicates a fault in the internal cooling fan circuit. When the logic board detects that a fan is not rotating at the specified RPM, it halts operation to protect internal components from heat damage. Often, this is caused by dust accumulation or a mechanical obstruction, but it can also signify a failed fan motor.

1 views

Common causes

  • 1Physical obstruction in fan blades due to dust buildup.
  • 2Internal fan motor failure.
  • 3Damaged sensor wire on the cooling fan circuit.
  • 4Faulty fan power control circuitry on the main board.

Solutions

Diagnóstico rápido

If your printer stops shortly after booting and displays E804, it is failing its self-diagnostic test regarding airflow. Check for excessive dust or debris near the printer's rear exhaust ports.

Solución paso a paso

  1. Power down the device and disconnect it from the wall outlet.
  2. Inspect all air vents on the back and sides for physical obstructions.
  3. Use compressed air to clear dust buildup from the fan grill area.
  4. Power on the unit; if the error persists, one of the internal fans may be faulty.

Prevención y mantenimiento

  • Airflow clearance: Keep a 20 cm gap between the printer and the wall at all times.
  • Routine cleaning: Vacuum the exterior vent ports every two weeks to prevent dust intake.
  • Room climate: Keep the printer in an air-conditioned office to maintain steady internal temperatures.

Cuándo llamar a un técnico

If cleaning the vents does not resolve the error, a professional technician must replace the failed fan unit. Attempting to disassemble the printer interior may void your warranty.

Ficha técnica del equipo

  • Technology: Color Laser Production Printer.
  • Speed: 65 ppm.
  • Connectivity: USB 3.0, Ethernet, WLAN.
  • Monthly Cycle: Up to 300,000 prints.
  • Compatible Consumables: Canon T01/T02 series toner.
  • Recommended Use: High-volume offices and print shops.
  • Official drivers / firmware

Steps to follow

  1. 1

    Safety Power Off

    Turn off the device and unplug it from the power source before starting any maintenance.

  2. 2

    Physical Inspection

    Check all air grilles for foreign objects or heavy dust accumulation.

  3. 3

    Dust Removal

    Use short, controlled bursts of compressed air to clean out the internal air paths.

  4. 4

    System Test

    Wait 10 minutes, power up the printer, and check if the error message is cleared.

Frequently asked questions

Yes. It can lead to internal heat accumulation, which might damage sensitive electronic boards and power modules.

Unless you are a trained technician, it is not recommended to disassemble the printer's core to replace fans, as it can void your service agreement.

Always use genuine Canon toner, as lower-quality third-party toners often shed excess powder that clogs printer fans.

Clean them monthly, or more frequently if the office environment is dusty or high-traffic.