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Rattlecan

Wiring a trailer light harness into a car ain't like it used to be.

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When I had the hitch receiver mounted on our new car a couple of weeks ago, I priced out getting the wiring kit installed while they were at it. I figured for a hundred bucks labour, I would do it myself and save the money.

 Didn't need the power plug right away anyway, cause we were just using the bike rack for our trip.

 Anyway, today I trundled off to U Haul and bought the wiring kit, and proceeded to crawl under the car in the driveway to hook it all up.

 The last car, made in 2008, I was able to just splice into the wires, solder and heat shrink, and it was all good right up until we dealt the car.

Long story short, it don't work that way any more. I got it done, and it works, and I'm happy I saved a hundred bucks, but mid way through the job, I was wondering why I didn't just pay it.

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I don't screw around with vehicle wiring anymore. Too damn complicated, think you're tapping into a hot wire and you short a computer.

I would stick with the factory, plugin harness now a days. 

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I think I've decided against putting a hit (unwired) on my car.  They'd need to take the bumper off to mount it to the frame.  THe bumper has an amazing amount of integrated electronics in it.  It will take the shop a whole day to do it.  Too much risk for me.

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5 minutes ago, Further said:

I don't screw around with vehicle wiring anymore. Too damn complicated, think you're tapping into a hot wire and you short a computer.

I would stick with the factory, plugin harness now a days. 

I did use a custom fit harness from Curt. It is plug and play connections with the exception of the live wire that you have to run to the battery, so you really cant connect it wrong. 

It's just a struggle fishing one line of the harness up through the cavity behind the body panel, removing the left tail light to plug the T harness between the light and power cord, another branch of the harness goes between a plug behind the left rear wheel, and then route the live wire up front.

Actually wouldn't be a bad job with a lift, but rolling around under the car on my back with the back wheels up on ramps wasn't fun.

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1 minute ago, Rattlecan said:

Actually wouldn't be a bad job with a lift, but rolling around under the car on my back with the back wheels up on ramps wasn't fun.

Every time I change oil, I ask myself why. But it's a good excuse to take a peek at her (the cars) bottom

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2 minutes ago, jsharr said:

I just bought a receptacle to fit the hole in my bumper and attached it to the w oh ring harness connector.  

Doh! Now you tell me. I always end up doing things the hard way.

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38 minutes ago, Further said:

I don't screw around with vehicle wiring anymore. Too damn complicated, think you're tapping into a hot wire and you short a computer.

I would stick with the factory, plugin harness now a days. 

...the last car electronics class I took here (a year or two ago) was a revelation.  I used to have an ASE certification in auto electrical. Had the official patch on my coveralls and everything.  This class was heavy on controller area networks, and the different types.  I was kinda lost during a lot of it, but so was everyone else, (I think :) ).

The tools and software just to do a diagnosis any more are pretty well beyond the reach of us shade tree mechanics. And those little individual computer modules all over the car that are linked together and get information from each other are expensive as hell is you fry one.

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10 minutes ago, Rattlecan said:

Doh! Now you tell me. I always end up doing things the hard way.

I assume all trucks are prewired.

When I worked at the boat dealership we carried quick connect wiring harnesses for a number of vehicles.

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9 minutes ago, Page Turner said:

...the last car electronics class I took here (a year or two ago) was a revelation.  I used to have an ASE certification in auto electrical. Had the official patch on my coveralls and everything.  This class was heavy on controller area networks, and the different types.  I was kinda lost during a lot of it, but so was everyone else, (I think :) ).

The tools and software just to do a diagnosis any more are pretty well beyond the reach of us shade tree mechanics. And those little individual computer modules all over the car that are linked together and get information from each other are expensive as hell is you fry one.

A couple of years before I retired from the road, my truck was struck by lightning just after I had parked for the night just outside Chicago and was crawling into bed. In the old days, a little thing like that would not even have been a hiccup. The worst that might happen is you might have to finish the trip without a radio, but in this case, it fried every ECM in the truck, and I had to be towed home.

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1 minute ago, jsharr said:

I assume all trucks are prewired.

When I worked at the boat dealership we carried quick connect wiring harnesses for a number of vehicles.

Maybe it came with a towing package from the factory?

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3 minutes ago, Rattlecan said:

Maybe it came with a towing package from the factory?

Many cars have a connector inline you simply open andplug a t adapter into

 

t1_150.jpg

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15 minutes ago, jsharr said:

Many cars have a connector inline you simply open andplug a t adapter into

 

t1_150.jpg

I've seen simple T harness like that for pickup trucks, but they have to make life a little more difficult for the rest of us.

This is the unit I installed.

https://www.etrailer.com/Custom-Fit-Vehicle-Wiring/Kia/Sportage/2019/C56321.html?vehicleID=201949295

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8 hours ago, Rattlecan said:

I've seen simple T harness like that for pickup trucks, but they have to make life a little more difficult for the rest of us.

This is the unit I installed.

https://www.etrailer.com/Custom-Fit-Vehicle-Wiring/Kia/Sportage/2019/C56321.html?vehicleID=201949295

While I had U-Haul put the wiring on a Corolla due to time constraints (approaching hurricane, no truck rental available but plenty of trailers for Home Depot plywood run), my preference is etrailer where bought the hitch from for a bike rack. Skipped the wiring harness because who is going to pull a trailer with a Corolla. 😮 What I really like about etrailer...even if not purchasing from them, is illustrated by the Kia link above. It has a video for most products describing the product and how installed, and sometimes a second video of an actual install. Additionally, towards the bottom is a pdf download of the illustrated installation instructions. 

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8 hours ago, jsharr said:

I assume all trucks are prewired.

When I worked at the boat dealership we carried quick connect wiring harnesses for a number of vehicles.

Don't assume that they are prewired. Many trucks don't even come with a towing package to support the stated (or higher) towing capacity if intending to tow a large item like a travel trailer or large boat. That is a huge risk/unknown when buying a used truck and requires extra research based on the VIN to see how originally equipped. Tow packages usually contain more than just the hitch, like heavier cooling, alternator, brake controller, etc. Dealer's buyers agent typically doesn't check the box for the factory installed, typically $750, towing option and it becomes apparent when can't find the first one on the lot.

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I think the new plug and play ones are easier, but I also used to install car stereos so I got used to fumbling around in tight spaces hunting for wires long ago.

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The wiring harnesses I buy from Autozone for my Hondas access from the trunk or hatch/tailgate and are all plug in. No splicing required. I don’t plan on putting a hitch on the Oddesey so I haven’t looked into if that is even possible.

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11 hours ago, Square Wheels said:

I think I've decided against putting a hit (unwired) on my car.  They'd need to take the bumper off to mount it to the frame.  THe bumper has an amazing amount of integrated electronics in it.  It will take the shop a whole day to do it.  Too much risk for me.

Did they not offer a factory installed trailer hitch as an option when ordering? A lot of times BMW USA won't on cars with a notation in the owner's manual "towing - not recommended" despite BMW DE and BMW UK having marketing material showing the vehicle pulling a trailer. Thinking of the X1 (same chassis/engine/transmission as my Mini Countryman) that BMW DE shows a X1 pulling a heavy ski boat at a press event in the Alpines. I guess in the USA the corporate lawyers limited liability by declaring the vehicle couldn't do what it can do. 🙄 Was actually at the BMW dealership yesterday (researching RV alternatives - Class C or travel trailer) looking at X5 (vs Mercedse GLE, Jeep Grand Cherokee, Audi Q7) with towing capacity above 5000 lbs (7200-7700lbs in this case). While the X5 is impressive none had the optional $550 trailer tow...and searching throughout the State, there was 1 in the entire State! Basically would have to special order a new factory build and wait if I went that route. Mercedes, over 50% had the towing option.

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11 hours ago, Rattlecan said:

I've seen simple T harness like that for pickup trucks, but they have to make life a little more difficult for the rest of us.

This is the unit I installed.

https://www.etrailer.com/Custom-Fit-Vehicle-Wiring/Kia/Sportage/2019/C56321.html?vehicleID=201949295

I've done a couple of these. Both on Jeeps after adding the hitch.  30 minutes tops and that included finding the zip ties in the basement. 

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My parents were too poor to own a car, but I realized I'd need one to commute to college and drive to a job to work thru college, so in my senior year of high school I got a fast-food job and a '59 Chevy Impala for $300.

It had a 283 cu.in. V8 engine and, even though I knew virtually nothing about cars, between friends and the library I figured out how to replace the leaking manifold gaskets, use a 2-barrel carburetor rebuilding kit, replace the exhaust pipes and muffler, install an 8-track player, etc.

Today, I know much more about cars but would be stumped at doing almost any of that because of electronic complications or the fact there's not much room around anything to work in.

Additionally, it seems like the cars are designed so that you can't use simple tools so you have to have it serviced at a garage.  Some playing kids apparently bumped into my parked '97 Taurus's side view mirror and broke its housing. The local Ford dealer wanted $300 to fix it or $150 for the electronic-adjustable mirror and housing.  I got a new OEM unit on eBay for $60.  I had no trouble popping-off the door's interior upholstery but there were three bolts/nuts holding the unit in place. One of them was, for NO structural reason, hidden behind a strip of metal bracing in the door.  If my brother-in-law's extensive auto tool collection didn't include a specialized flexible wrench that would grab the hidden nut, I'd have never been able to get the broken unit off.

 

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3 hours ago, Tizeye said:

Did they not offer a factory installed trailer hitch as an option when ordering? A lot of times BMW USA won't on cars with a notation in the owner's manual "towing - not recommended" despite BMW DE and BMW UK having marketing material showing the vehicle pulling a trailer. Thinking of the X1 (same chassis/engine/transmission as my Mini Countryman) that BMW DE shows a X1 pulling a heavy ski boat at a press event in the Alpines. I guess in the USA the corporate lawyers limited liability by declaring the vehicle couldn't do what it can do. 🙄 Was actually at the BMW dealership yesterday (researching RV alternatives - Class C or travel trailer) looking at X5 (vs Mercedse GLE, Jeep Grand Cherokee, Audi Q7) with towing capacity above 5000 lbs (7200-7700lbs in this case). While the X5 is impressive none had the optional $550 trailer tow...and searching throughout the State, there was 1 in the entire State! Basically would have to special order a new factory build and wait if I went that route. Mercedes, over 50% had the towing option.

They do not have an option.  It would seem there is one company that makes it for my car.  It cost 500 to buy and another 500 to install.  That's way more than I'd want to spend.  Looks like all of my rides will be from my front door now.

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4 minutes ago, Square Wheels said:

They do not have an option.  It would seem there is one company that makes it for my car.  It cost 500 to buy and another 500 to install.  That's way more than I'd want to spend.  Looks like all of my rides will be from my front door now.

Check U-Hall.  Most of the better one's offer hitch's and installation.

Also check Curt.  https://www.etrailer.com/vehicle-finder.aspx?HHCat=hitch&HHYear=2019&HHMake=Mercedes-Benz

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3 hours ago, Square Wheels said:

They do not have an option.  It would seem there is one company that makes it for my car.  It cost 500 to buy and another 500 to install.  That's way more than I'd want to spend.  Looks like all of my rides will be from my front door now.

Roof rack.

Many BMW's have a permanently installed, expensive, bicycle as a roof ornament

Just remembered, convertible....   

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7 hours ago, Tizeye said:

Did they not offer a factory installed trailer hitch as an option when ordering? A lot of times BMW USA won't on cars with a notation in the owner's manual "towing - not recommended" despite BMW DE and BMW UK having marketing material showing the vehicle pulling a trailer.

Looks like BMW UK has no problem sticking the dick on the outside of the BMW for a change :D

image.thumb.png.ea17d1f8efe069be3fc97ceba078c1e4.png

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4 hours ago, Razors Edge said:

Looks like BMW UK has no problem sticking the dick on the outside of the BMW for a change :D

image.thumb.png.ea17d1f8efe069be3fc97ceba078c1e4.png

That is actually the European style hitch, and in the US what Execuhitch (a/k/a Invisihitch outside the US) and Stealth hitch. Those are the $500+ hitches SW referred to. It is a unique design. Instead of the 2" receiver opening that is part of the hitch design protruding out for the receiver, it has either the ball or 2" receiver attachment that slides up and locks vertically in the mounted hitch. Supposedly stronger and doesn't have the forward/aft play during acceleration/braking.  But they are expensive. Curiously, Stealth is new and undercuts Execuhitch on price...but both are located around Atlanta. Disgruntled employee setting up competing company????

 

Also noted when looked at etrailer, BMW 3 series hitch for current years was totally missing, so the standards - Curt, DrawTite, etc apparently don't make one and the eurostyle hitches are the only option. Must have been a chassis change with the latest 3 series. Quick review of Bimmerfest Forum notes same, and discussion of Execuhitch vs Stealth tended to favor Stealth.

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