Extuder/Electronic Fans not working

[ryaneb85]

So, I upgraded to the Noctua fans a while back and never got the the electronics and extruder fans running. I thought it might have been a dodgy connection but didn't have a change to do too much digging, but now I have, everything looks ok. The problem is the fans still don't want to play nice.

I upgraded the firmware a while back and I'm wondering if the M108 command is now obsolete, as when I try to enter M108 S255 the fans do nothing. Either M108 is no longer valid, or I do have a bad connection somewhere.

Can anyone advise whether M108 is still active and should start/stop the 12V fans?

Ryan

[Jules]

Jin told me back when I first switched to dual....M108 is a non-standard code and it wasn't implemented in the newer versions of the firmware.

[ryaneb85]

hmmm. Then that might answer that mystery. So when and how should my fans switch on?! I've just started a PLA print and nothing has switched on yet

[Jules]

hmmm. Then that might answer that mystery. So when and how should my fans switch on?! I've just started a PLA print and nothing has switched on yet

You have the bed fan set in the slicer software? (It usually kicks in at layer 2.) The extruder fan will turn on automatically and turn off automatically based on the extruder temperature in the new firmware.

[ryaneb85]

bed fan is working fan. electronics enclsoure and extruder fans are not turning on at all, no matter what temperature the hot end is at.

[Jules]

Uh-oh! (You are now beyond my expertise, except to say....check the connections, which you have already done.)

[jsc]

The wiring harness for the extruder/case fans changed at some point, they went from 12V fans wired in series (to split the 24V), to become 24V fans wired in parallel. I think. Which harness do you have, and is it hooked up correctly? If they are two 12V fans, you should have the ground from the case fan wired to the positive input on the extruder fan.

Also, depending on your firmware, the extruder fan will not turn on until the extruder reaches a certain temperature.