No ground on trailer plug

Okay, so getting things set up for the GF and I to go snowmobiling this weekend, I got to the point where I test the trailer lights and I get nothing.  Trailer is her father's, so we spent several hours trying to figure this out.  We started with grounding on the trailer... which wasn't far from the problem.

Anyway, it boils down to the fact that my 2011 Z71 with integrated trailer brake controller has a dead ground post in the 7-pin plug.  This is all factory wiring.  I've got an extended warranty, but it has a $100 deductible.  I'd rather not fork that over. if this is a mostly simple fix.

My questions are- can anyone tell me the location of the ground to body termination for the trailer harness?  Has anyone experienced this problem before?



I'm really close to just cutting the ground wire and soldering on an extension then terminating at whatever body location I feel like.

it is grounded to the frame G400 #1 in pic

Okay, great!  That's easily accessed.  I was hoping it was that back body mount.  This should be a fairly easy fix then assuming the problem isn't in the plug itself.


Wish I didn't have my quad all torn down in my garage with some other items- I'll be doing this outside tonight.  Guess I'll have my propane salamander going!

Are you sure it is not a fuse?
The trailer connection has 3 or 4 fuses underhood.

Update:

Spent about an hour and a half working on it thursday night.  Started with cleaning up the ground terminals on that rear body mount; covered them in dielectric grease and put it back together- still a dead ground pin.


So that meant it was the wire or the receptacle.  I had a hard time believing it was the wire so I got back down and looked at the back-side of the receptacle... Turns out the trailer wiring harness on the truck plugs into the back of the receptacle for the plug and harness from the trailer.  I got that unplugged (it had a good bit of resistance despite fully depressing the retaining device).  When I got a look at the terminals on the plug, I immediately saw the problem.  There is only one terminal in the plug that is not a square pin; it's a spade style... its supposed to be brass but was covered in green... and it leads to the ground.  Got that all cleaned up and gave all terminals a heavy covering of dielectric grease and put it back together.

Long story short, if you're having a ground problem at your trailer receptacle, work your way back- pull the plug off the back of the receptacle and see if everything is clean.  Despite being a gasketed plug, somehow moisture had still made its way in and went to work on that one terminal.