[tommymc]

I'm getting ready to install a trailer hitch and wiring on my 2016 Rav4 LE. This is something I've done to almost every car I've owned in the past 40 yrs, and am pretty comfortable with the process. I mentioned to my (Toyota trained) mechanic that I was going to pull the trailer wiring out of my old car and install it in my new Rav4. He warned me against this, saying that people have had electrical issues caused by non-Toyota harnesses, and it would void my warranty for any electrical problems.

I do notice one difference between my old trailer wiring and the new ones being sold at eTrailer and similar sites. The new converter modules apparently draw their power directly from the battery. The product descriptions suggest this is to prevent potential overload. My old one(s) were passive, and drew their current from the lines to the brake and blinker lights.

Is this true? I have an identical non-powered module wired into my 2010 Rav4 with no issues. Have the the newer electrical systems somehow become more sensitive or lower amperage? I assume that tapping into an accessory line would not be an adequate power source, and running a line into the engine compartment is going to be a massive pain. Has anybody had experience with this? Thanks.

 

[Francesco]

Depending on the number of trailer bulbs it can damage the computer. Running the wire from the back to the battery is not a difficult job. On my 2015 I opened the door sills on the rear passenger side and fed the wire up to the spare tire jack area where I retrieved it. I ran the wire up to the front through the door sill and into the engine compartment. There are some good videos on some of the trailer sites that show how to access the taillight connectors. I did not want to run the wire under the vehicle. If you run up the passenger side the battery wire is not going to be long enough so I purchased I think 20 feet which I ran and then spliced in the rear. If I had to do it again I would attempt to do it on the drivers side using the door sills.

Frank 2015 Rav4 XLE AWD with 20K miles

 

[tommymc]

Thanks Francesco. So must be the newer models have more sensitive computers. Or maybe I just got lucky on my 2010. It sure makes me miss the good old days. I guess a new module is in my future, as well as some snaking wires.

 

[Bent Nail]

Yes, it would appear that a powered module is in order, whether it is to protect the rather small gauge wiring or the computer, I cannot say.

https://www.etrailer.com/t1-2016_Toyota_RAV4.htm

 

[mmorgan1865!]

I just installed a Curt hitch and wiring on my 2016. The module had a separate wire that ran all the way to the battery. I had the car on a rack so I ran the wire underneath to the battery.

 

[Quickdtoo]

I used the OEM routing of the aftermarket wiring kit 12V wire on my 2015 which is inside along the driver's side, I didn't care for a hot wire running underneath where it can get snagged when offroad, there's already too many soft points under there without adding another concern. Moot issue on the hybrid tho with the 12V battery under the rear deck.

 

[tommymc]

Just a follow-up. I ended up buying a Curt hitch and a T-One powered wiring harness from eTrailer. Hitch installation was a breeze and all the holes lined up. The wiring vehicle-specific wiring harness was a lot easier than probing for wires like I've always done in the past. I ran the hot wire inside the car, similar to the video above. It was easy to route the wire through the door-sills and up to the front. Getting through the firewall was a royal pain. Although the position of the firewall gasket/grommet is in the same location as the video, my 2016 has body parts that completely block access to it. It's so buried that I had to lay across the front of the engine just to be able to get a partial view of it. At about 9:20 in the video, you can see the "nipple" that the wire has to feed through. I tried to pierce the nipple from the inside but couldn't get the hole big enough for the wire to thread through. After a lot of fussing, I was able use a bent coat-hanger to turn the nipple inside-out and pull it into the car. Then I could reach up under the dash and cut it with an exacto knife and push it back through. It was difficult, but I feel a lot safer with the hot wire inside the car.