Non-Tow Package Trailer Wiring
11-28-16, 09:39 PM
#16
Intermediate
Well, I just had a couple of interesting conversations... the first with Lexus to identify my Factory/Port build details, and the second with the Lexus dealership which installed my towing hitch receiver.
Regarding the original factory build, there was no documentation to suggest that my RXh received the Tow Package (only the Comfort and Premium packages), yet there is definitely an external transmission cooler installed.
Regarding the Tow hitch receiver installation, that work did NOT include the transmission cooler, oil cooler, OR tow wiring controller -- it ONLY included the hitch receiver at the buyer's request for a bike/luggage rack. I actually spoke to the same Service Advisor who managed that ticket 6 years ago, and he says (as others have stated here and elsewhere in CL) that Lexus recommends to NOT tow with the hybrids anyway because they will run a little hotter than the conventional 3.5L engines. Now, the Sa says the hybrids run hotter, but they use the same coolant thermostats as the non-hybrids, so I can;t really see how they run hotter on an overall basis.
Consequently, the transmission cooler must have been a factory installation, but if that is the case, why in the world would the factory install an external transmission cooler and NOT install the external engine oil cooler, especially given what the SA said about the hybrids running hotter anyway??? It's a mystery we will never know, nor does it really matter very much in the end.because I'll be using my F250 diesel for my towing needs.
I thought that this investigation would bring some closure to me, but it has only left the mystery in place, but now with even more questions than I had before.
Regarding the original factory build, there was no documentation to suggest that my RXh received the Tow Package (only the Comfort and Premium packages), yet there is definitely an external transmission cooler installed.
Regarding the Tow hitch receiver installation, that work did NOT include the transmission cooler, oil cooler, OR tow wiring controller -- it ONLY included the hitch receiver at the buyer's request for a bike/luggage rack. I actually spoke to the same Service Advisor who managed that ticket 6 years ago, and he says (as others have stated here and elsewhere in CL) that Lexus recommends to NOT tow with the hybrids anyway because they will run a little hotter than the conventional 3.5L engines. Now, the Sa says the hybrids run hotter, but they use the same coolant thermostats as the non-hybrids, so I can;t really see how they run hotter on an overall basis.
Consequently, the transmission cooler must have been a factory installation, but if that is the case, why in the world would the factory install an external transmission cooler and NOT install the external engine oil cooler, especially given what the SA said about the hybrids running hotter anyway??? It's a mystery we will never know, nor does it really matter very much in the end.because I'll be using my F250 diesel for my towing needs.
I thought that this investigation would bring some closure to me, but it has only left the mystery in place, but now with even more questions than I had before.
I'll guess that the cooler came on the assembly line and after they realized that the worker installed it on a vehicle it wasn't specified for, they made the decision to say "screw it - I guess Mr Owner gets a free tranny cooler" rather than slow the assembly line to have him remove it. This would also explain the other missing ancillaries for towing. Maybe...
Feel better? LoL!
11-29-16, 05:10 AM
#17
I'll guess that "run hotter" could still be accurate in that perhaps they work harder and generate more heat, requiring the same thermostat and cooling system to work harder to keep it in the specified range. Maybe...
I'll guess that the cooler came on the assembly line and after they realized that the worker installed it on a vehicle it wasn't specified for, they made the decision to say "screw it - I guess Mr Owner gets a free tranny cooler" rather than slow the assembly line to have him remove it. This would also explain the other missing ancillaries for towing. Maybe...
Feel better? LoL!
I'll guess that the cooler came on the assembly line and after they realized that the worker installed it on a vehicle it wasn't specified for, they made the decision to say "screw it - I guess Mr Owner gets a free tranny cooler" rather than slow the assembly line to have him remove it. This would also explain the other missing ancillaries for towing. Maybe...
Feel better? LoL!
Those were some of my thoughts as well. Feel better? Not really. Do I NEED to feel better? Not really. I'm quite satisfied, overall, with what I have.
02-06-17, 12:43 PM
#19
Moderator
That square hole is part of the trailer hitch. You could have any shop remove it for less than the dealer. It is only 4 bolts. Probably half hour labor.
You could sell it on Craigslist. That is how I found mine for $100. However, it does stiffen up the rear a bit, only weighs about 20 pounds and adds to resale value.
You could sell it on Craigslist. That is how I found mine for $100. However, it does stiffen up the rear a bit, only weighs about 20 pounds and adds to resale value.
02-06-17, 01:42 PM
#20
Ok this is great news! I thought it was welded on the frame... do you know if the bottom part of the rear bumper is cut out for the trailer hitch? I ordered an F-sport should be here next week... im hoping its below the bumper and not cut through it... thank you in advance
02-07-17, 06:53 AM
#21
Moderator
bdman360 - From your questions it sounds like you do not even know what your vehicle looks like, go outside and look at the rear bumper and hitch. Do you own this vehicle?
What year is your RX with the hitch? All the third gen ones (2010-2015) have the hitch below the rear bumper. The only part cut out is part of the under cladding under the car which will not be visible if you remove the hitch. There is no hole in the bumper. The hitch receiver is barely visible below the bumper. here are many photos online and on this forum.
However, if you are getting a new vehicle, why bother with removing the hitch from the old one.
What year is your RX with the hitch? All the third gen ones (2010-2015) have the hitch below the rear bumper. The only part cut out is part of the under cladding under the car which will not be visible if you remove the hitch. There is no hole in the bumper. The hitch receiver is barely visible below the bumper. here are many photos online and on this forum.
However, if you are getting a new vehicle, why bother with removing the hitch from the old one.
02-07-17, 09:48 AM
#22
bdman360 - From your questions it sounds like you do not even know what your vehicle looks like, go outside and look at the rear bumper and hitch. Do you own this vehicle?
What year is your RX with the hitch? All the third gen ones (2010-2015) have the hitch below the rear bumper. The only part cut out is part of the under cladding under the car which will not be visible if you remove the hitch. There is no hole in the bumper. The hitch receiver is barely visible below the bumper. here are many photos online and on this forum.
However, if you are getting a new vehicle, why bother with removing the hitch from the old one.
What year is your RX with the hitch? All the third gen ones (2010-2015) have the hitch below the rear bumper. The only part cut out is part of the under cladding under the car which will not be visible if you remove the hitch. There is no hole in the bumper. The hitch receiver is barely visible below the bumper. here are many photos online and on this forum.
However, if you are getting a new vehicle, why bother with removing the hitch from the old one.
i found a picture online but it was a non-f sport
02-07-17, 10:26 AM
#23
Moderator
bdman360 - When you have the trailer package it does not include the hitch itself. It only includes a transmission cooler, upgraded alternator and trailer hook up wiring. You have to buy the hitch. Thus, this is a non-issue. There will not be any trailer hitch on your new vehicle. You should have said this was all for a new vehicle and you could have asked the sales folks.
The following users liked this post:
bdman360 (02-07-17)
08-29-17, 12:51 PM
#24
Driver School Candidate
Join Date: Dec 2016
Location: Utah
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
My 2010 RX350 may be an oddball, but I don't have the towing package, yet on the basis of the pre-wiring at the drivers-side rear fender and the presence of a fuse in the right slot, I bought a Curt 56083 connector and Curt 56081 connector tester. I figured I'd just return the connector to Amazon if it turned out I needed the full wiring package. Anyhow, long story short, it works. Mine is a Japan-VIN car, which may or may not make a difference. And since I'll use it for no more than a bike rack or light utility trailer, I don't see the need for the additional cooling and charging stuff.
08-31-17, 12:45 PM
#25
Intermediate
My 2010 RX350 may be an oddball, but I don't have the towing package, yet on the basis of the pre-wiring at the drivers-side rear fender and the presence of a fuse in the right slot, I bought a Curt 56083 connector and Curt 56081 connector tester. I figured I'd just return the connector to Amazon if it turned out I needed the full wiring package. Anyhow, long story short, it works. Mine is a Japan-VIN car, which may or may not make a difference. And since I'll use it for no more than a bike rack or light utility trailer, I don't see the need for the additional cooling and charging stuff.
You just mean that based on its VIN, it appears to have been assembled/built in Japan as opposed to USA or Canada, right?
12-30-17, 10:11 AM
#26
Driver School Candidate
Join Date: Dec 2017
Location: CO
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
Non-tow package trailer wiring
I just bought a 2013 RX-350 without the tow package that has the hitch installed that the original owner had installed for a bike rack. I need to know how to add the wiring harness for a trailer. Sounds like this thread dead ended without much help. Probably have to go to Lexus to get an answer but I am looking if anyone knows.
K
K
12-31-17, 06:28 PM
#27
Manufacturers save money using one wiring harness for the build.
Then when an option is declined a harness plug may not be used but, it is still there (dangling or tucked away).
On the left rear (outside) underneath is a plug to attach the wiring harness that goes to the trailer.
On the right rear (inside) near the taillight when the hatch is open is another plug dangling. you have to remove interior padding to see it.
That is where the computer goes, there is a hole to mount it.
You can buy the computer on line for around $100 (Part Number PT219-48101-TC)
A picture of the computer will make the plug and mounting self explanatory.
Easy screwdriver job.
Also check the fuse location under the hood for 'Trailer Lights', my '15 already had a fuse there.
05-17-18, 05:27 AM
#28
Driver
Thread Starter
I just bought a 2013 RX-350 without the tow package that has the hitch installed that the original owner had installed for a bike rack. I need to know how to add the wiring harness for a trailer. Sounds like this thread dead ended without much help. Probably have to go to Lexus to get an answer but I am looking if anyone knows.
If just plugging in the end harness doesn't work, did you need to check to see if there is a fuse installed, if so you probaly don't have the converter, therefore you need to install the converter provided in the full kit you bought.
This is the link to the full kit:
http://amzn.to/2eo76xj
Think is the link to the end harness for tow packaged vehicles with the converter already installed: https://amzn.to/2rPJJ4x
Goodluck with your install.
Last edited by tdott; 05-17-18 at 05:44 AM.
09-01-18, 07:44 PM
#29
FUSE for TOWING
Im interested in installing tow package on my 2013 rx350. Hitch and wiring harness.( no problem to install)
Which fuse slot am I using? (Slot #44, Tow Batt., 20A) or (Slot #45, Towing , 30A) or both?
Thanks
Which fuse slot am I using? (Slot #44, Tow Batt., 20A) or (Slot #45, Towing , 30A) or both?
Thanks
Thread
Thread Starter
Forum
Replies
Last Post