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Side fans wont turn on

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I printed a 40 hours print over the weekend that came out fine.

I tried to start another print, but noticed that the side fans didn't come on. The speed was at 100 % in the tune menu.

I checked the wires and the green connection was broken.

I fixed it, but when I tried to check the fans again, there was a noise like a short-circuit and it smelled like that too.

I checked the wiring and they are as they should be.

Is there a way to check the connections/main board, in case the problem is somewhere I can't see?


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Yes, and click "raw" to get the pdf. Go to page 55 of 69 and in top right, step 16, examine the colors of the 3 wires related - one wire (green in photo) should connect the two fans together to make them "in series".

Smell of smoke is a very bad sign.

Check the voltage at the fan connectors - each fan should be 12V (24V across both fans). If one fan is shorted or open you will see 0V across one fan and 24V across the other.


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