Fan control speed ?

  • Hi there,

    My hephestos is giving some trouble:

    I can't control the cooling fan speed. It is either off (M106 S0 or M107) or at full speed (M016 Sxxx). I can't get it running at a percentage value.

    I'm running the lastest firmware, tried with latest CURA and simplify3D.

    Is this normal (seems a basic feature to me) ? Is it a board issue ? Or am I doint something wrong ?



  • MVP

    This is normal. In hephestos firmware only works at 0% or 100%.

  • Well that's a bit odd..

    However for those interested here's the workaround:

    - Download latest BQ firmware
    - Open Marlin\Pins\pins_BQ_ZUM_MEGA_3D.H
    - Edit the following lines:

    // Cooling Fans
    #define FAN_BLOWER_PIN 2 // old 12
    #define FAN_BLOCK_PIN 6 // old 11


    // Auxiliar Power Channel Driver
    #define AUX_DRIVER_PIN 12 // old 2

    - Open Marlin\Marlin_main.cpp
    - Search for "M106"
    - Edit the following lines:

    #if defined(FAN_PIN) && FAN_PIN > -1
    case 106: //M106 Fan On
    if (code_seen('S')){
    if(code_value() > 0)
    //#if IS_RAMPS
    fanSpeed = code_value();
    // fanSpeed=255;
    else {

    - Compile and load with the make.cmd following the documentation
    - rewire your blower fan to "AUXFAN"
    - rewire the extruder fan to "E1FAN1"
    I switched both so I can keep the 2x2 connector, you just need to swap + and - to have correct polarity, see pics:

    Tadaa you have fan % control

  • MVP

    Great, this way we can use the bq firmware.
    There is another way, using original Marlin compiled for this machine.