UMO+ Fan Power Issue ... Help?

[KAMSCMrC 0]

I need help/ideas with a fan problem on one of my two 18 month old UMO printers. The current situation is this. When I plug a brand new Ultimaker Fan into the controller board I get the following symptoms:

1) if I turn the machine on, nothing initially happens.  However, if I give the fan a little start, it will continue to turn slowly, as though a moderate amount of power is coming through.

2) if I use the controller to turn the fan speed up to 255, it will not have enough power to start on it's own, but if I give it a little start with my finger, it'll turn faster than in scenario one, but nowhere near normal full fan speed.

3) I have tested the new fan on another printer and the fan itself is fine.  I have also updated to the July 2017 Firmware, but the issues persist.

 

The background of how I got here is below.  What I'm wondering is: 

A) are there any known issues or suggestions for approaching this that might help me?

B) is there a way I can use the LED Power port instead of the fan port to get around this issue (maybe by switching ports in the firmware somehow)??

C) are there any other creative tests/solutions anyone can suggest?

 

BACKGROUND:

At some point, I had fan blades break on this printer (from stray plastic on a bad print) and had to replace the fan. At the time, I could not find the Ultimaker fans anywhere and bought another fan. We were very careful about correct size (they fit) and voltage (24V). The new fans worked for quite a while (weeks or months) and then ceased to work. I recently got the Ultimaker Fan and today I ran the tests described above.