Fan does not turn off


i print with a Tronxy X5SA Pro

I noticed a very strange phenomenon. I printed the exact same gcode once via SD card and once via Octoprint. When printing via SD card, the mainboard fan goes out after printing and not via Octoprint.

My end code looks like this.

M107 T0
M104 S0
M104 S0 T1
M140 S0
G92 I0
G1 E-1 F300
G1 Z + 0.5 E-5 X-20 Y-20 F9000
G28 X0 Y0

Can anyone explain to me?

Greetings Tobi


M106 S0

instead of M107 T0

Tbh I don't even know if the M107 T0 command exists - the documentation only mentions T1 to T255

Unfortunately does not work

You said it's the mainboard fan.
Is it activated in the start gcode? Or is it temperature controlled?
There is usually no gcode for controlling a mainboard fan.

1 Like

the mainboard fan starts turning as soon as the first stepper motor starts moving. It's just not clear to me why if I print the same gcode via SD card that the fan then goes out after successful printing and not via octoprint

Just to be sure : the fan you're talking about is in the control box ? Not the fan located near the hot-end, nor the one in the power unit ?

As said by @Ewald_Ikemann, there's no gcode to control fans in the control box or the power unit. Hypothesis : it is probable that the manufacturer of your printer has embedded in their firmware a detection to shut down the fan when the printer start idling, which is detected when the file on the SD Card is fully read; Octopi will not send such a thing, and so it will not trigger the fan shutdown.


My Ender 3s mainboard fan was in parallel with the parts cooling fan.