Hot End Heaters Calibration (PID Autotune)

Model [] AON M2+ (CE) [] AON M2+ (R-NZ) [] AON M2+ [] AON-M2 2020 [] AON-M2
Category [ ] Preventive [ ] Corrective [] Calibration


The procedure that follows gives instructions on how to calibrate the two hot end heaters with the use of the Proportional Integral Derivative (PID) autotune control loop. Correctly calibrated hot end heaters will help with print quality.

The PID autotune calibration procedure must be done when the heater block assembly is repaired or changed.

Estimated time: 15 minutes


None required.

Parts Information

None required.

Personal Protective Equipment

Qty Description Minimum Specification
1 Safety Eyewear ANSI/ISEA Z87.1

PID Calibration Explained

M303 [C<Count>] [E<index>] [S<temp>] [U<flag>]

  • M303: Input the M303 command with the necessary parameters.
  • [C<Count>]: Number of cycles. The minimum amount of heat cycles is 3. AON3D recommends a heat cycle of 5.
  • [E<index>]: The selected hot end heater to be calibrated. Input E0 for the left hot end heater and E1 for the right hot end heater.
  • [S<temp>]: Target temperature (in degrees Celcius). Input the target temperature for the material to be used.
  • [U<flag>]: Use PID result. Automatically enters the PID values into the firmware after the PID autotune procedure is complete.


M303 C5 E1 S220 U1

The right hot end will be cycled five times at 220°C and automatically saved to the Electrically Erasable Programmable Read-only Memory (EEPROM).

The PID values for low-temperature ABS, PC, and nylon materials (200ºC to 300ºC) will be different than for high-temperature materials (300ºC to 450ºC+ for Ultem™, PEEK, and other high performance materials).

PID Calibration Procedure

Use the Graphical User Interface (GUI)/web browser as follows:

  1. Select Settings > Terminal.
  2. Input the M303 command with the necessary parameters.
  3. Let the machine run the command.
  4. The GUI/web browser will show:
    • Completed after the selected hot end end has been successfully done.
    • Completed when the PID values have been successfully saved.

Last modified: January 25, 2023