I think I shorted my layer fan


  • administrators

    Is it just the fans that are not working, or more than that?

    If it's a revision 1.03 or 1.04 Duet, have you checked the 1A fuse?



  • something happened, smoke, the + hot end fan path melted the coating off then no lights either. where is the 1amp fuse/what is it labeled? and I don't know the revision but its says straineffector v1.3 cerl ohl 1.2


  • administrators

    I assumed you were using a Duet WiFi or Duet Ethernet, so I meant the Duet revision. The 1.03 and 1.04 revision Duets have a 1A fan fuse.

    If the layer fan shorted on the Smart Effector, or you connected the fan with the wrong polarity, then the PCB traces between the 6-pin connector and the fan connector may have fused. If so then you can bypass them with wire links. There should be continuity between HF+ on the 6-pin connector and + on the Hotend Fan connector, and similarly between HF- and -.



  • oh yes i was using the maestro board, with the hotend fan and layer fan disconnected the lights arent working either. i fear i may have destroyed it somehow. but at least the probe still words.


  • administrators

    Do the stepper motors still work? Does the Always On fan output of the Maestro work?



  • so it would appear that everything on the meastro board is working while everything on the smart effector is working EXCEPT the lights and both fans (i routed around them to test them)


  • administrators

    Do fans work when you connect them direct to the Maestro?



  • yes they do, i must have somehow melted something in the smart effector pcb that is shorting out the fans and lights. Are they routed together or very next to eachother?



  • Idk if this is already dead, but now they work, but as with before they dont work when placed underneath the smart effector and attached to the heat sink and layer cooling duct respectively. But before I attach them, same plug and everything just not mounted, they work fine, no loose wires either. Thoughts?


  • administrators

    Bad solder joint on the 6-pin connector? Or bad crimp joint where the cable plugs into it?



  • So I got the hot end hotend fan working fine, but I did a continuity test on the layer fan wires straight from the maestro and it said there was no continuity, is there something to replace on the maestro? or a work around? ps thank you so much for your help dc42


  • administrators

    Where exactly was there no continuity?

    Does the layer fan work if you connect it to an always-on fan output?



  • The lack of continuity appears to have been my misunderstanding of how the continuity test works, sorry for muddling things up.
    The part fan does work when connected to the "always on". There appears to be a bubble on directly above the D18 lettering on a chip named F3 ED with to lines at the bottom of it. if that is the problem should i either A) try to remove and replace(which seems like a bad idea given my inexperience) or B) is there a way to change the pins from fan 0 to fan 1 in the firmware, or something to achive similar results?


  • administrators

    If it's a 3-pin chip that looks damaged, then it's probably the fan mosfet. Removing it without damaging the PCB requires either hot air rework equipment, or low-melting point solder such as ChipQuik.

    Here are a couple of firmware options:

    1. In your M563 tool definition command(s), use the F parameter to specify a different fan. Then that fan will be used as the part cooling fan whenever that tool is selected. If you issue M106 commands without a P parameter when no tool is selected, the command will still be routed to fan 0.

    2. If the second extruder heater output is free, you can reroute fan 0 to that. In your config.g file, use command M307 H2 A-1 C-1 D-1 to disable heater 2. Then use command M106 P0 A2 to redirect fan 0 to heater 2 output.



  • sorry for being a bother but this is weird when I tried adding F1 to the end of the line "M563 P0 D0 H1" and connected it to fan 1 I can increase and decrease the fan speed but it won't turn off.
    Now when i added
    M307 H2 A-1 C-1 D-1
    M106 P0 A2
    under "custom settings" and changed the fan to the heater 2 it would ONLY turn on and only for a second when I changed the fan speed.


  • administrators

    Fan 1 is configured to thermostatic mode by default, because it is normally used to control the hot end heatsink fan. So you need to disable thermostatic mode to use it as a normal fan.



  • Worked like a charm thank you for all the help.


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