Wiring Up Brake Controller

[Jeffwouldgo]

Hello! My wife and I finally pulled the trigger on a 2018 LC and we love it. We are eager to start towing with it and I wanted to pick anyone’s brain regarding the harness. I have a 2015 tundra that it was plugged into that I thought would plug straight into the LC but realized when I opened the glove box it’s a different style.

Anyone have any ideas what color goes where? My brake controller is a reliance and as you can tell I’m not all that savvy.

 

[RET2]

It's not by glovebox but over by OBD port area. Google it, there are detailed pics

 

[Jeffwouldgo]

Sorry I meant to say the wiring harness I found in the glovebox. I believe the port for it is in brown tape under the dash. Thank you!

 

[Sandroad]

You may not need the controller wiring that was in the glove box. It looks like the white end of that wire and the white end of the wire you pulled from the Tundra are the same. If so, all you do is plug the white end of your controller into the existing socket in the Land Cruiser, mount the controller, and go towing. The existing socket is under the dash fairly high up on the far left side. There are numerous threads on finding and using the socket, so run a search on MUD with the term brake controller. If you need additional help, post back.

Edit. Now that I more carefully read your post, I see you noted the connector is different. You will have to either splice the LC connector onto your Tundra connector or get a harness from Reliance. Google the color coding to get the splicing correct if you have to do that.

I use a Tekonsha P3 controller that plugged right into the LC.

 

[Cruiser17]

You will connect the brake controller's wiring harness to the factory harness matching the following colors.
Black to black — 12V power.
Green-Yellow to Red for brake light signal
White-Black — White for Ground
Yellow to Blue for brake controller output

The Green wire in the factory harness will not be connected. It is for a backlight and the controller will not need this separate function.

 

[Fisher23]

The white plug attaches under the dash on the driver side.

There is an adapter (2) plugs available. You plug in to that white plug you have and then into the white plug on the LC.

It's way up there.
You need to open up the dash so that the switches and the buttons on the lower left are hanging out and then the white plug where it attaches is behind them plugged into a dummy dead-end plug.

There is another thread about this, and that's where I found out where the white plug hooks up.

You don't need that factory harness with the white yellow green brown wires.

 

[Fisher23]

The white plug attaches to a white connector which is behind this panel with the switches. The plug is on the left against the wall