PWM part cooling fan not working

#1
When connecting a part cooling fan to the blower fan pins, I can't get the fan to run even when the fan speed is set to full speed. The fan was working last week, but after I did some maintenance on the hot end, the PWM fan pins stopped working. When I connect the fan to the LED light pins, the fan works fine at full speed. Has anyone else had this issue? Could I have blown a mosfet in the board?
 
#4
I contacted gCreate support about this issue. To diagnose the problem, I connected the fan directly to the main board. The fan worked perfectly with PWM control. This showed that the problem was the connection between the main board and the fan. I have not diagnosed the issue further, but I suspect it is a broken wire in the ethernet cable, or a connection issue in the connectors. For now I ran a separate wire directly from the main board to the fan. Hopefully my trials and errors can help someone in the future with a similar issue.