In the driver's side access panel in the rear of the vehicle is a plug with a green/yellow trace wire that is constant battery positive and a black wire that is ground. It doesn't appear to plug into anything I have optioned on the vehicle. Does anyone know what this was used for so I know what fuse it is using and also is there any reason why I cannot use this to connect to my little 12v socket/USB panel to run my Fridge while camping in 2 weeks? Thanks.

 

Have you checked the wiring diagram?

 

I think it’s there exactly for that purpose, but as min says, check the wiring diagram for the fuse size and make sure your draw will be less.

 

Okay, I found a better electrical manual that has actual pictures of the connectors along with the color codes instead those worthless diagrams. It appears this connector C0691 is for rear A/C. Not sure why the yellow/green wire is always hot but atleast now I know where to start looking for the fuse. Here's a link. https://discoii.files.wordpress.com/...al-library.pdf

 

I think rear ac is a 25A fuse so that should be plenty to run your fridge and usb charge port. Nice find because I also wanted additional aux power in the rear and re-purposed the rear cig adapter. I would make certain the fridge has a twist-lock connector that stays put because mine kept popping out so I cut that crap off and use XT60 connectors; another good option are the red/black 15/30/45A rated Anderson Power Pole connectors.

 

I've got lots of auxiliary electrical stuff on my truck and I would HIGHLY recommend swapping out that 12V plug for an Anderson power pole connector (powerwerx.com, if you are looking for a good source). Those 12V "cigarette lighter" style plugs are notoriously loose stuff gets rattled loose all the time, they weren't originally designed as power interface plugs. I wouldn't want my fridge to get disconnected 30 minutes into a 4 hour trip!