About to wire my 7-way connector

[jaevans]

Greetings all,

I am about to wire in and install my brake controller, to include the 7-way connector at my hitch. We don't have a trailer yet but am wondering if I should bother with hooking up the purple/aux wire to the reverse/backup signal at my tow vehicle tail lights. What other possibilities exist for the use of the aux signal?

Any recommendations for this?

Thanks in advance.

John

[Darral T.]

I'd have to ask why you WOULDNT want to hook up the backup lights. Wait until you arrive at a campsite AND/OR home at night and have to back in and you will regret not having them working. I'd rather not have my TOW b.u. lights working than my trailer. It's hard enough to back as it is. And if you're HAVING to back up at night without lights.... well... I dont know of ANY other purpose anyone would be using the wire for.

Dunno what advice others will give, but from nearly 6 yrs of pulling my Scamp, I can advise you to hook up ALL the lights!! I have a cam that looks out the back window of my Scamp and the backup lights are enough to aid me with the camera...another addition I HIGHLY recommend for ANY travel trailer.

[jaevans]

If the majority of fiberglass trailers have backup lights, then yes, that is the route I will take. It just seems odd to me that a ton of references show this as not being connected at the tow vehicle connector.

[Darral T.]

Older rv's may not. But I have a 2010 13' Scamp and I made sure they were on there when I ordered and wouldnt want to be without them. Anyway, if I was hooking up another 7-pin and even if I knew my trailer did NOT have bu lights, the wire would still be there in case the next one I own did.

But that's just my preference and opinion. And on these forums, opinions differ as much as buttercups and garlic!!

[jaevans]

It is only a little extra work running a wire from the backup circuit and if I discover any conflicts down the road with any trailer, I will have installed a bullet connector so it is easily disconnected - another easy solution.

[Darral T.]

Not sure what other "conflicts" you could run into unless someone has pulled away from a "standard" hookup on a trailer. Maybe others know where this has happened and have used the wire for something else. I'd be afraid of it. It's a backup wire and that's that. To me, that would be like a trailer reversing the signal lights or something.... I'd make my trailer line up with the 7-pin standard personally.

[Larry C Hanson]

Hello,

My Trillium has after market LED backup
lights installed. They are great for after
dark trailer parking. I would hook up
the wire. If you get a trailer without the
lights they are an relatively simple install
and worth the effort.

Larry H

[Darral T.]

I want to make sure we're all on the same page here. There are TWO wires that he could technically be talking about: The "aux" wire which to me could be the 12V wire that keeps the onboard RV battery charged. Then there's the backup wire.

jaevans: Look at my wiring layout that comes on the Scamp and see if this is matching what you're hooking up at your 7-pin socket on your tow vehicle. Notice the CENTER of this 7-pin is for the backup. If it's the other, the "aux" as you call it, it COULD be used to charge your trailer. Look at it and we'll go from there...

https://www.flickr.com/photos/50351683@N08/9728844401/

[Carol H]

Originally Posted by jaevans

Greetings all,

I am about to wire in and install my brake controller, to include the 7-way connector at my hitch. We don't have a trailer yet but am wondering if I should bother with hooking up the purple/aux wire to the reverse/backup signal at my tow vehicle tail lights. What other possibilities exist for the use of the aux signal?

Any recommendations for this?

Thanks in advance.

John

Not sure what vehicle you are having the 7 pin installed on but in many/most cases the shop doing the install will use a pre made/manufactured wiring harness for that vehicle to do the job and tap into what ever wiring the auto manufacture pre wired at the factory - many cases its nothing more than a 4 pin hidden behind a rear light or in the truck someplace. If the installer uses a pre made wiring harness the aux wiring will most likely be on it so not likely there is anything to be saved in not hooking it up.

[thrifty bill]

+1 Depends on the tow vehicle. My Honda Element has a four wire trailer kit that is plug and play. Vehicle is prewired for it, easy to install.

Meanwhile, my 2010 F150 is prewired with both a seven wire plug and a four wire plug. Really nice setup. They also had trailer brakes as a factory option, original owner did not spring for that. So I will be installing the OEM trailer brake controller, its plug and play too, but part of the dash has to be removed to install it.

[jaevans]

Originally Posted by Carol H

Not sure what vehicle you are having the 7 pin installed on but in many/most cases the shop doing the install will use a pre made/manufactured wiring harness for that vehicle to do the job and tap into what ever wiring the auto manufacture pre wired at the factory - many cases its nothing more than a 4 pin hidden behind a rear light or in the truck someplace. If the installer uses a pre made wiring harness the aux wiring will most likely be on it so not likely there is anything to be saved in not hooking it up.

I installed the hitch, 4-way wiring, transmission fluid cooler, and power steering cooler, as I will the brake controller and wiring. Our 2004 Honda Pilot had a wiring harness and connector for a 4-way to which I only had to connect a 4-way adapter. I will now only need to wire to the backup lights and run a 10-gauge cable for 12V and the brake controller signal to the engine compartment and then connect to the controller under the dash.

I've already run the cable while visiting a hobby shop with a lift. The rest I should be able to do this weekend with breaks.

john

[Darral T.]

For what it's worth John, www.etrailer.com has some excellent information, parts AND vids on cabling and installation of these 7-pins, controllers etc.

[jaevans]

Originally Posted by Darral T.

For what it's worth John, Trailer Hitches & Vehicle Accessories (800)298-8924 has some excellent information, parts AND vids on cabling and installation of these 7-pins, controllers etc.

Thanks Darral,

That's where I purchased all the parts and kits That may actually be my source of earlier confusion as they don't use the purple backup light wire.

I am good to go though with the project.

John

[jaevans]

HAHA - now I know why etrailer omitted the purple wire connection to the backup light signal. The tail lights are in the rear columns in my 2004 Honda Pilot. The backup lights are in the tail hatch. So the wires run up inside the hatch to the top/hinge and connect internally to a harness. I'd have to pull the headliner (I think) to access the harness.

I will ping folks on the Piloteer's forum and see if anyone else has done this. Worse case, I could run a wire along side my 12v and brake signal 10-gauge cable to the engine compartment and connect to the backup signal there but I am hoping there is an easy way.

Thought you'd all enjoy this.

John

[Thinh]

...If you do the wirings yourself, it's better to have back-up wires @ stand-by mode, i.e...you can hook up back-up camera, flood-light or sound alarm when the trailer going reverse in future. My Trill has flood-light and sound-alarm when it is in reverse, with the option turning of either one or both of them.....Share with you.

[jaevans]

Originally Posted by Thinh

...If you do the wirings yourself, it's better to have back-up wires @ stand-by mode, i.e...you can hook up back-up camera, flood-light or sound alarm when the trailer going reverse in future. My Trill has flood-light and sound-alarm when it is in reverse, with the option turning of either one or both of them.....Share with you.

I was able to route a wire behind the hatch seal along the rear pillar, so now I have a wire to connect to the purple reverse/aux wire on the 7-way.

Could you clarify what you mean by standby mode?

I know I can get alarms/adapters that plug in where the backup light bulbs plug in, so that isn't a huge issue, but I am curious about a flood light option.

Thanks,
john

[Joe Romas]

One other use for the center pin (backup lights) I've seen is to lockout the surge brakes while backing on a boat trailer.
Boat trailers seldom if ever have electric brakes for obvious reasons.

[jaevans]

As a final wrapup, I was able to finish the installation and the brake controller gives some indications that it is working. I have no trailer yet so I can't fully test it out, though the Air Force Academy will do that for me as a preliminary requirement to renting any of their campers or trailers, so I will schedule that sometime in the next week or so.

Now I am ready for a FG camper when the golden purchase opportunity arises.

Thanks all,
John

[Thinh]

Originally Posted by jaevans

I was able to route a wire behind the hatch seal along the rear pillar, so now I have a wire to connect to the purple reverse/aux wire on the 7-way.

Could you clarify what you mean by standby mode?

I know I can get alarms/adapters that plug in where the backup light bulbs plug in, so that isn't a huge issue, but I am curious about a flood light option.

Thanks,
john

What I meant in stand-by mode is to have spare wires already connected in case of future uses. Clearly label them or mark them in case years later you won't be confused(my case anyway)...