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Discussion Starter #1
I bought the Trailer Wiring Harness for the 2006 Rav4 Part #08921-42900. It is quite a piece of work and includes:

- The main harness that goes from under the dash to the left rear tail light area


- Sub harness #1 which has a standard 4 pin trailer connector with mounting bracket at one end and plugs into the main harness, at the other end.


- Sub harness #2 is used to tap into the power to supply the converter. For vehicles with the tow package this harness is not used because a plug that goes into the main harness is already there and draws power through a 30A fuse in the fuse box under the hood. For vehicles without the tow package, the sub harness is used to tap power through a 15A fuse in the box under the dash. Both fuses are provided.


- A converter box that mounts in the left rear behind the side trim panel. It converts the separate brake lights and turn signal lights on the Rav to shared brake and turn signals for the trailer. It also protects the tow vehicle from any electrical faults on the trailer. This is actually more than a converter, it is also an isolator and uses a separate, fuse protected circuit to supply power to the trailer lights.

This is different from previous Rav's that drew power for the trailer lights from the tail light circuit. I talked to an installer who wired a new Rav using the traditional type of converter and he said that it worked but the airbag warning light would not go out with the trailer connected. He ended up using a Modulite Trailer Light Module that works exactly the same as the Toyota converter and also requires a separate power supply.


This is the complete harness with the supplied plastic ties and sticky foam tape used to hold the harness in place. Following the harness from the trailer connector at the left side we have:
- trailer connector
- grey plug into main harness
- grommet to protect the wire where it goes inside
- two white connectors used to tap into the left rear tail light to get left turn, lights and stop signals for the converter.
- converter
- ground connector
- two white connectors used to tap into vehicle harness for right turn signal
- small white connector to 12V for converter


The Trailer Wiring Harness does not come with installation instructions so I went to the service department of the dealership where I bought my Rav and politely asked them to print a copy of the instructions off their computer. They printed all 28 pages for me and would not even accept a donation to the coffee fund for the trouble.

The book time to install the harness is 2 hours which is probably a good deal for most people. I will be doing it myself because I also have to install a brake controller and trailer battery charging circuit and the wires for these will follow the same path as the harness.
 

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Thanks for the post Harold! I'm a bit confusd tho, and it could be cuz you're working with a Canadian install which the tow prep pkg is included on all models which may be different than the US models. The US tow prep pkg says it includes a 7-pin connector, but I don't see that in your detail, is that an additional part? Below is the quote from Toyota.com in which there apparently is at least one error, the HD alternator is supposed to be a 150A. I don't have mine yet, supposed to take delivery tomorrow if they get the hitch and mud guards installed. Mine was inbound when I bought it, it has the tow prep pkg w/o hitch and I got the dealer to install the hitch and wiring harness for $450, total was $1000 over invoice.

Thx,

Tim



Tow Prep Package w/ 3500-lb. towing capacity includes Converter Class 4 Hitch, Heavy Duty 130A Alterrnator,Transmission Oil Cooler & 7 Pin Connector(TO)
 

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Discussion Starter #3
I got my wiring harness from the USA and it has the same part number a the one sold in Canada. I think that the newer Toyota trucks, such as the Tundra, have a connector under the dash that includes the brake pedal signal and power for the brake controller. I was hoping that the Rav would have this as well but I crawled under my dash the day I brought my Rav home and was unable to find one. I suspect that the 7 pin connector listed as part of the tow prep package is a mistake. I wish it were not.

The only place that I can see a 7 pin connector being used on the Rav install is where the trailer plugs in to the tow vehicle and it would replace the 4 pin trailer connector. The 7 pin connector includes pins for trailer brakes, trailer battery charging circuit, and one extra often used for trailer back-up lights. These are in addition to the normal lights, left turn, right turn, and brake lights. I wil be using a 7 pin trailer connector on my install but there is not much point if you don't have a trailer brake controller installed at the same time.

The hitch and wiring harness including supply and installation for $450 is a fair price for what is involved. If you can, please mention the 7 pin connector reference to the mechanic who does the actual install, see what he says, and let us know.
 

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That's really odd cuz every new vehicle I've bought in the last 15yrs has had a 7 pin connector included with the tow pkg, that includes the prewiring for the brake controller under the dash. They even included a 7 to 4 pin adapter! But none have been a Toyota, this is my first.

I'll post tonight what I find out..... hopefully!!! It's been a long time since I had to wait for a new vehicle, the last time was in 1969 when I ordered a Ford Maverick whilst in Viet Nam!!

Thanks for the follow up,

Tim
 
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I've found at least 2 different versions of what the tow package includes:

The brochure lists the following components as part of the tow package:

* Upgraded radiator
* Upgraded alternator
* Upgraded fan coupling

HOWEVER, when I go to buyatoyota.com and enter my zipcode, I get the following components in the tow package (and it's impossible to option a V6 without the tow package in Colorado):

* Class IV hitch
* Heavy duty 130A alternator
* Transmission oil cooler
* 7-pin connector

My guess is that the first description is more correct. I've not seen a RAV4 that includes a receiver, and it certainly wouldn't be a Class IV. And, as we've seen, it certainly doesn't include a 7-pin connector.

As far as the transmission cooler goes, I bet that either all V6 RAV4.3's have them, so it's not needed as an "extra" in the tow package, or it is a similar setup to the Sienna where the cooler is built into the radiator.
 

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Discussion Starter #6
Quickdtoo said:
That's really odd cuz every new vehicle I've bought in the last 15yrs has had a 7 pin connector included with the tow pkg, that includes the prewiring for the brake controller under the dash. They even included a 7 to 4 pin adapter! But none have been a Toyota, this is my first.


Tim
It may be that the 7 pin connector for the brake controller is there but I just didn't see it. I will be using a Tekonsha Prodigy brake controller and it can plug directly into a 7 pin tow package harness using the 7 to 4 pin adapter that you mentioned. The adapter is usually included with the vehicle and is usually found in the glove box but I got nothing like that with my Rav. I can also buy a Toyota to Prodigy adapter separately if the 7 pin connector turns out to be there. The factory repair manuals and wiring diagrams are not available in Canada yet or I would check and see where to look for the connector.
 

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The parts guy did say that whatever comes with the tow prep pkg that needs to be dealer installed, will be in the glove box and that hitch receivers are a dealer installed item, so you won't see a newly delivered R4 with a hitch. In his parts book, it shows 2 receivers, one for the tow prep pkg R4 and one without.

Here's another curiosity....the Toyota parts store which supposedly sells OEM parts, shows 2 hitches, a 1500lb and a 3500lb....dealer only shows as stated above.

http://www.toyotapartsstore.com/default.php?cPath=12_187&sort=3a&page=2&osCsid=08c85d31e0f9cc108a572e0a6fcbf5b5

Tim
 

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Took delivery at noon, the connector is a 4 pin just as you show in the pic. Fortunately, all of my trailers are 4 pin. :wink:

I'll need to pul the underbody shields to see what kind of tranny cooler it uses, there isn't one ahead of the radiator that I can see, just the a/c evaporator. I suspect it's going to be an in-radiator type which I don't really want to rely on. All older vehicles had those and external coolers were the rule for towing. Maybe the internal coolers are more efficient now, dunno.

Tim
 

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I bought the simple connector harness for my hitch, but haven't installed it yet. Didn't have the warm and fuzzy feeling about it and wanted to wait until I could find more information about using that type.

I've been thinking about going the OEM route since I don't want to screw-up the electrical system in the RAV...

A big thanks for sharing the info you have. I think I'll be returning my harness and paying the extra bucks to get something I know will work.

Please let us know how the install goes. Take photos if you can.
 

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Harold, Thanks very much for the info please keep us posted with the install. I will be doing the same thing probably in the next month or so.

Harold: I will be doing it myself because I also have to install a brake controller and trailer battery charging circuit and the wires for these will follow the same path as the harness.
Definitely keep us posted on how you made out with this....

Thanks again
 
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wiring harness

I am a little confused. If you purchase the towing package you still would be required to run this harness from the glove box to the hitch ? Seems like they would already have that done! My Rav is on order but am trying to determine if I will be able to install the wiring and hitch. The hitch looks pretty easy but I am not sure about running that harness.
 

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Discussion Starter #12
You are still required to install the Trailer Wire Harness, even if you have the Tow Prep Package. It actually goes from under the dash on the driver's side to the hitch not from the glove box. You may be thinking of the European harness which is a different kettle of fish entirely. I agree that the trailer wire harness should already be installed but I'm sure that there is a profit based reason for not doing so.

The toughest part about installing the harness is removing and reinstalling all of the interior components without breaking or scratching anything. The second toughest part is sticking your head under the dash far enough see where the harness connectors plug in. I had to use a mechanics mirror this morning to locate the plug that provides the right turn signal power. I have not installed mine yet so I don't know of any other pitfalls. I was just poking around to see where everything is which, believe it or not, is my idea of fun.

To see if you are up to the job, why not get a copy of the installation instructions from your dealer and walk yourself through them. If you can't understand exactly what needs to be done and where, it is probably wise to pay someone else to do it.
 
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I installed the wire harness

I got the wire harness #08921-42900 a few weeks ago, but finally got the guts to take apart my new RAV4 and install it yesterday. It took me about 4 hours, but I could probably do it again in about 2 hours. I made a few dumb mistakes that cost me time, but didn't break anything! Oh, when removing the bolts for the shoulder straps, the seats do slide out of the way. One piece of advise: don't use that European installation manual that is on this website because there are significant differences. The US one is easier. For one thing, the bumper does not come off. What you want to do is either get your dealer to print out the installation manual, or do like I did and go to the Toyota TIS (http://techinfo.toyota.com) and pay $10 for one day access, then print out the installation manual. After having studied both the US and the European installation manuals, I give a lot of credit to the European one for clear pictures and ease of use. To bad those writers didn't produce the US one.
My vehicle is the V-6 with the "tow package". Why the factory didn't install the wiring ahead of time is beyond me. Having the tow prep does save one step.... You don't need to install the short single red wire power cable that comes in the kit. Its already there tucked under the dash along the left side, so you just plug in.
My overall impression is that it was easier than I was expecting. If I were to do it again I would definitely go with this factory kit... 30A of power, no cutting of wires, circuit overload protection, no warranty concerns.
 

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Pre Wired

I'm quoting directly from the optional equipment list off of the price sticker that was removed from the rear window.

"Tow Prep Package - V6 3500 lb. Towing Capacity - Includes Upgraded Radiator, Fan Coupling, Alternator, and Pre Wiring"

So, where the heck is this pre-wiring?

BTW - no transmission cooler.
 

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Discussion Starter #17
Re: Pre Wired

thecat said:
So, where the heck is this pre-wiring?
The only pre-wiring that I have found on the Rav so far is the wire going from the passenger side fuse box under the hood to a connector under the dash by the driver. To me, trailer pre-wiring means at least a connector for the lights located at the rear of the vehicle. The end user then purchases a 7 ft long harness that goes from this connector to the trailer. We get this only by adding the trailer wiring harness. At best, pre-wiring includes the above plus a connector under the dash that plugs into a trailer brake controller. I think that this is standard on the Toyota Tundra truck. I am waiting until I can get a factory wiring diagram manual to see if there is more trailer pre-wiring on my Rav than I have found so far.
 

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Judging by the contents of the installation guide, having the "hitch pre-wiring" saves you about seven steps, or three pages of procedures, involving running an additional wiring sub-harness under the dashboard and installing a 15A fuse. :?
 
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