Fan PWM Broken...

[brentwerder 12]

Just got back to work on my Ultimaker Original Plus: my dual 40mm 12V fans have stopped working.  One of the fans had seized up, and I bought replacements to fix the issue.  However, after soldering the new one in place, they wouldn't run.  They're wired in parallel.

 

The wire going from the board to the fans is OK, just tested that.  I'm not sure if the Fan PWM output on the board isn't good anymore, or what.  I tried testing the voltage of it when the fans are on at 255, but I'm not sure what the normal voltage is.

 

-Brent

[neotko 1,400]

 

[brentwerder 12]

Thanks for the reference.  I picked up 10 of those diodes from Digikey (in case I screw up soldering a few times).

 

In the meantime, so I can get back up and running, I think I'll try to reroute my fans to the LED PWM.  How exactly did you do that?

 

Thanks.

[brentwerder 12]

Just replaced the board with a spare I had sitting around, and the Fan PWM on that board was working fine, although one of my fans wouldn't start up until I hit 255 PWM.  Weird, since I bought a new set of the exact same fan from Amazon.  Any clue what's going on with that?

 

Unfortunately, there's another problem: the 24V J19 output (next to the power supply) is busted.  It reads 0V, so my always-on fan won't work.  Is there another spot on the board I can grab a constant 24V from?  Or would it be possible (sorry, not an EE) to use the GPIO outputs to do that when the temp is above 50C or something?  My Prusa does something similar to that.