No output from battery stud #2

Discovered I do not have power from Stud #2 in my 2012 Yukon Denali XL. I have the integrated trailer brake so one red/black wire was already connected and I confirmed the trailer brakes were working and I was able to set the appropriate gain prior to towing. Wanted to connect the 12V charge wire (which I believe is incorrectly labeled in the below pic - there is another red/black stripe wire below the master cylinder that I believe is the charge wire). Used a voltmeter to measure the output from each stud and determined that stud #2 did not have any output - stud #1 was fine with output around 13. So I hooked up the charge wire up to stud #1 (in addition to the already connected integrated brake wire) and confirmed power to my connector, so it's charging my TT batteries now.

Questions:

1. Whats the possible cause of no power to stud #2? (I checked most relevant fuses)
2. Since I do not need to hook up the aftermarket brake controller wire, are there any issues to be concerned about with no power from stud #2?

I think you need to put in a big 30a fuse in the box also for that to work, if I remember correctly

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

The fuse was what my NBS needed for the charge line.

EDIT: and on the NBS the charge line is always active; I would think your year works the same (YMMV). When stopped for longer periods of time I have to remember to unplug the trailer connector in order to not discharge the truck battery.

And, of course, to plug it back in before leaving.

Yup you need two fuses if you want to use those posts. One was for the trailer brake controller, the other was for the aux power line to the 7 pin connector. It's probably fine and you just need the fuse. I would hit it with some sand paper first to clean it up. If you haven't used it yet, it might be a little corroded.

my 2012 didn't need a fuse, try checking again for voltage on the bottom plate instead of the bolt

Doubeleive said:

my 2012 didn't need a fuse, try checking again for voltage on the bottom plate instead of the bolt

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Did you buy it used?

Here's a nice video on it all:

Derick said:

Did you buy it used?

Here's a nice video on it all:

Click to expand...

yes, but it had never been hooked up the wires were still factory wrapped and tucked away, one owner by some corporation in Nevada

Clay, send me an email and I'll send you the upfitter's guide which shows how all this stuff works and how to hook it up. [email protected]

Alternately, all of this has been covered on here before and can be found through searching. You need a 40 Amp J-Case fuse to activate that circuit. It goes into the empty slot just to the right of the right side stud.

swathdiver said:

Clay, send me an email and I'll send you the upfitter's guide which shows how all this stuff works and how to hook it up. [email protected]

Alternately, all of this has been covered on here before and can be found through searching. You need a 40 Amp J-Case fuse to activate that circuit. It goes into the empty slot just to the right of the right side stud.

View attachment 221770

Click to expand...

Sent you an email - thanks!

Was the 30A fuse for stud #1 actually.