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Hot End Fan not spinning  

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Hot End Fan not spinning

OK, I'm a smidge lost on what to test with my mini+ hot-end fan failing (the equivalent of the noctua on the MK3). The fan works if I plug the cable into a 5VDC source, disconnected from the buddy board (runs at much higher-speed than it does when printing). It does not run regardless of hot-end temperature. Did something blow on the buddy board? Is the fan fused? I only see the 1 3A fuse (I assume that tiny fan isn't drawing 3A and that that is for the bed heater). The thermistor is working fine for the nozzle temp (or at least seems reasonable when I tell it to heat up) so this isn't a thermal runaway. Is something blown on the buddy board? I don't mind replacing either the fan or the buddy board if that's the issue, but I'd hate to do all that if it's something simple. The symptoms began for about a week prior to the failure the fan would run at full=speed (loudly) whenever the hotend was hot, then one day simply didn't turn on anymore (I first thought it must have failed from over-driving but since it runs just fine with a +/-5VDC connection the fan still works (unless the speed controller in the fan is what failed?)

Posted : 21/06/2022 1:38 pm
RE: Hot End Fan not spinning

Is it an original fan? If it is not and it's consumption was higher than allowed, it could be the power tranzistor blown up. 

even an old man can learn new things 🙂
Standard I3 mk3s, FW 3.10.1 RC1, MMU2S, no closed box, Fusion 360, PrusaSlicer, Windows 10
PRUSA MINI FW 4.3.4, Prusa Connect Beta

Posted : 21/06/2022 6:40 pm