How to wire for double towing

[FSAD]

So I've done some searching on here and I'm not finding much on the actual method of setting up the brakes on the second trailer. Perhaps that's just me...

For starters, let's just assume I've done all the research on IF I'm allowed to double tow, and I know all the laws for the states I'll be traveling. And, let's assume I know what I am doing as far as HOW I will double tow.

Now that that is covered, let's get to the nitty gritty of the brakes.

I have a Tekonsha P3, which has "Electric trailer brake control for up to 4 braking axles".

So... do I just tap into the first trailer's pigtail and send a few more wires back for the second trailer's brakes and lights? Or do I need multiple controllers, wires for the second trailer to come from the "home" base of the tow vehicle, or any of the other things I've read people do?

I feel like if I just tap into the first trailer's wiring and send basically a second set of wiring back to the second trailer, that should work fine, providing I use a heavy enough gage wire, etc

thoughts?

[nevadanick]

I would tap into the brake wires and go try it. I ran wires the length of my trailer instead of trying to get inside the back wall. You dont fix sway with brakes by the way, you load right and it doesnt happen. I have been towing 2 bumper pulls for years now and its a great way to take everything we need.

[KD4UPL]

I would want 2 brake controls, 1 for each trailer. The trailers will likely have different weights, different brakes, etc. Being able to individually apply the brakes on the rear trailer can be very helpful in stopping sway.

[Francesca_Knowl]

Assuming that both trailers have electric brakes:

Majority opinion at another thread on this subject is that each braked trailer should have its own brake controller- this due to different settings required for efficient braking of each.

Evidently, it's felt that the "multiple axle" language on controllers applies to those axles on a single unit.

Link to that discussion.

[Bipeflier]

The lights were run up inside the rear wall to the 5th wheel tail lights.

The brakes were tapped in at the rear axle.