where do you attach white ground wire

Assume I'm dumb but I am installing a brake controller on my 2015 tacoma OR v6 with towing. I've located and attached the connesctor. I now need to ground the wire. Where?

 

Behind the kick panels there is a bolt behind there to ground stuff to. Just learned from a member installing my heated mirriors.

 

I Just installed a brake controller on a 2013 Tacoma. I'm assuming you are talking about the trailer ground wire on the harness provided with the vehicle? If that is the wire you are talking about it is wired to the brake controller. You-tube has some good videos on installation of a brake controller and that is where I got my information. There was nothing said about grounding it to the body.

 

Hi 4x4. No this is the white ground wire that comes with the brake controller connector. Need to ground it to metal, usually.

Unchained: dumb question but where is the kick panel? Do you mean the panel to the left of the emergency brake? If so, can I take it off?

 

The controller(Drawtite) I hooked up also has a white wire that, according to you-tube directions, connects to the brown, trailer ground, wire on the Toyota provided wiring harness. This is the wiring harness that was in the glove box of the vehicle I purchased, that plugs in near the parking brake peddle. There is no mention of connecting to another location, as I assume, the wire harness already is grounded.
Anyway a red light comes on when the manual button is pressed so I'm sure it is connected properly, although I haven't actually hooked up my camper to try it out. (may do that this afternoon)
Best of luck it's actually very simple to connect. Need wire butt connectors(4) and electrical tape and that's about it.
My vehicle is a 2013 model, but I doubt this has changed for 2015's.

Added note: The wiring harness has 5 wires and the controller has 4. The extra wire (green) that is for, headlamp switch to vehicle trail lamps, does not get hooked to anything, it is not needed.

Just hooked up to camper and took it for a spin and everything works fine. So the white wire needs to connect to the brown wire on wire harness.