Fan not working

Got my printer setup. Trying to run some tests with both PLA and ABS.
In the software you can manually set the extruder and the bed temperature. Next to it you can turn on the fan. I assume this is for the fan attached to the extruder. I can't get it to turn on. I can print though so is it needed? Also halfway through the print another fan seems to be turning on (under the printbed) is this for the power supply or something? I looked underneath but didn't open anything up.

 

It just helps on cooling layers. If you look at your slicer settings and cooling you'll see where it specifies when to use the fan or not.

Generally you'll be fine without it. Chances are it came disconnected. Take a peak at your ramps board for any loose wires. The fan is in the middle screw terminal. I believe D9.

 

You're right. Must have been a bad connection. Is working now.