tus

Does anyone have a set of chassis wiring diagrams for a 2013 RX?

The trailer light harness is out on my 450h. Since it's all under warranty and I needed my 40k service I took it to the dealer, where they somehow spent 3 hours doing the service and attempting to fix the harness while letting me sit "in the dark" in the waiting area. In the end I left without having the wiring problem fixed.

Specifically, I'm trying to figure out where the W1 and WP1 connectors are. According to what was entered in the history, that was the only thing that was checked.

To me this would be an easy problem. Since the tail/brake/signal lights all work properly I would guess that there is a signal getting to the back of the thing. From there you test the 3 parts that make up the system that gets the signals to the trailer , and connects to the chassis harness that's controlling the stuff that works. I'm wondering what this guy spent ~2 hours working on..At the very least I would have expected the guy to finish the 40k service and realized the wiring harness would take some time. At that point someone should have found me and ask if I wanted to stay or not.

Think I'll give them one more try to get this fixed and have to find yet another dealer. The description of the service I found online states that "THE CAR CAME INTO SERVICE VERY LATE IN THE DAY." I guess everything is relative, but to me 3PM should have given them plenty of time.

salimshah

For regular service it would be fine, but if there is a hard problem then it is considered late in the day.

Your warranty should cover loaner. Just schedule a repair appointment and drop your vehicle and take the loaner till they fix the problem.

Salim

tus

Already have a follow scheduled. Unfortunately I won't have time until after Thanksgiving.

Really wish they would have gave me the option of getting a loaner when they realized it would take at least 2 hours, and this doesn't count the 2 they already have in the job.

vlad_a

It's behind the right rear tail light. There's a towing lights controller that plugs in.
Here's an aftermarket unit I bought for mine (same as e-trailer). It'll make more sense what to look for once you see it:

There are 2 fuses under the hood. Make sure they are OK.

And then there's the trailer connector. That gets corroded real fast.

tn7con

It should be Rear Left (driver side,) correct?

tus

You have the harness that the trailer connects to, which in turn connects to a harness under the rear bumper on the drivers side.

There is also the control module which is located to the right of the spare tire well on the passenger side under the trim.

From the notes that were entered, it says the tech tested between the W1 and WP1 connectors. I'm wondering which connectors these are and where they are in the car. Given the time that was spent, I'm guessing the tech just started taking things apart instead of following the simple path from the trailer connector to the harness the controller is attached to.

vlad_a

No, it's on the right side. Of course, I started tracing wires from the left side when I was installing trailer hitch and connectors. Ended up taking both sides trim off.