Previous Owner Wiring Question

The previous owner has two power cables running directly off the battery, one didn't have a fuse in it so I'm not sure what it is powering but it looking like he plugged it directly into an OEM cable run, I put a fuse in the line and nothing exploded or turned on, pictures below any body have any ideas?? The power wire plugs into it directly from the battery near the back of the head lights, I tired to follow the cord but it looks like it goes in and under the truck - pictured below.



I tired to make an orange line that followed the wire so people could see where it went, not sure if that was helpful or not?




Also, no idea what this is for?? Sorry if this is a dumb question.

 

Well I answered one of my own questions, I was finally able to follow the wire to the truck bed and found a cut cable that goes to nothing hiding behind my rear wheel we'll, who knows, Still not sure about the second part thought. Thanks for your help

 

It's possible there was a shell at some point with lights? I know that's how mine was set up by the company that installed it, although they put a fuze close to the battery.

I believe that other button is for setting the Tire Pressure Monitoring system.

 

Other button is the reset for the TPMS as WATaco stated.