Hi,
I have a K mule 2014 model. Not ran it in a few months and when I tried the other month it would turn over but not fire. Tried again a few weeks later and it wouldn’t turn over but would click. Ran a Multimeter over the battery and low and behold it was dead. Removed it and Charged to 12 volts and whilst installing it noticed a black cable with a terminal attachment hanging loose. Have no idea where it came from. Traced it back and it appears to sit with a bunch of other cables with green, yellow and blue and seems to attach to black box behind what I think is the voltage regulator. Can anyone tell me where this should be connected? Should it be connected to the battery and if so what terminal? Picture shows cable and where it runs to.

 

Looks like that is a ground for your Battery .