Haldex info center (ABS) diagnostic

[Will47]

So I bought the haldex info center and plugged it in. Upon turning it on and clearing codes the only code that keeps coming up is (iso 191) ...so I looked up that code and it says that it is either a problem with the 15 amp fuse under the dash which I already confirmed is good.....or it could be the 7638 connector on the back bumper where you plug in power and abs to a trailer. I'm looking at the plug and I don't see anything burnt or wrong with it. Is there something I'm missing like another fuse or something like that? If it comes down to it I might just replace that connector on the back bumper in case it has an internal problem does anyone have a part number for that or at least where to find in the manual? I almost got her on the road this is literally my last hurdle thanks in advance y'all.