Stoplight switch wire for electric brake controller

I have a 2007 Toyota Highlander Hybrid. I have the Toyota trailer hitch and harness installed, it has the 4-pin flat connector. I've recently purchased a newer tent trailer that has the round 7-pin

connector. The RV dealer sold me a Tekonsha Voyager brake controller, and then realized that the vehicle is a hybrid and got gunshy about wiring everything up, said the grounding is different on the hybrids, etc. I did some research and think that their fears are about the high voltage system, not the 12V system.



I've ordered a kit off etrailer.com (ETBC7) that will convert from 4 pin to 7. The only thing that looks like it could be tricky is hooking up the stoplight switch to the brake controller. I can see the stoplight switch up above the brake pedal, but not sure how I'd get to the wires coming out of it to test which one is the correct one, and tap into it.



I found a set of installation instructions for the trailer wiring harness on a 2008 Highlander (http://www.howtopdf.com/?ytDa4Pfp), and it shows a converter being installed under the dash, and one of the wires leading to it is the one I need from the stoplight switch. Not sure if the 2008 wiring is the same or close to that for a 2007 model, at first glance I don't see a connector that looks like the one in the 2008 install instructions, but will try and cram my head under there and take a closer look.



Just wondering if anyone's done this before and/or knows a convenient place to tap into the cold side of the stoplight switch.

Reply 1 : Stoplight switch wire for electric brake controller

So I did some more digging around and after reading some other posts, it sounds like the towing converter is in the rear for a 2007 Highlander. I pulled out the tool compartment on the drivers side and found a black box with a multi-pin plug but have not found a wire that appears to be the brake / stoplight signal. There's a whole mess of connectors and wires back in this section, so I think I'm in the right area. Expect it would be less convenient to route another wire from the back to the front to signal the brake controller, but should be doable.



From what I had read on a wiring diagram I got from a Toyota technician, I thought that the blue wire would be the stoplight input signal to the converter, but it seems to have 12 V on it at all times.



I also tried to remove the lower dash panel (kick panel?) on the drivers side to see if I could get at the stoplight switch easier by doing that, and two tabs came undone easily, the ones above the coin drawer that hides the fuses. But I couldn't wiggle anything loose on the other side of the panel.