Trailer Wiring Tech...Need some help

[corsair23]

Coming down to the wire...Probably should have tackled this first but it is not near as glamorous as the ARB install

On my LX the PO installed a hitch and wiring harness. The hitch was a Draw-Tite and the wiring harness is the 4 pin type like this.

I had noticed a green wire coming off my battery going toward the back of the vehicle previously so tonight I investigated this a little more. Well, tucked in the back DS pocket (with the tool case and and bottle jack) is a "Draw-Tite Modulite Lite Trailer Light Power Module". Apparently this little gizmo is designed to provide power directly from the battery to the trailer lights through the plug. The model I have is the 18187 model, or the "Lite" version. Oh, and I don't think the PO put an in-line fuse on it either

Ok, so now I want to install my brake controller and it is all pretty straight forward until I get to the 'blue wire' for the trailer brakes. The instructions are pretty slim (read that as non idiot proof) and just state that the blue wire is run back to the trailer plug.

Well, with a 4-pin plug there isn't an open place to run that blue wire to. Does that mean I need to convert over to a 7 pin/pole plug like this: 4 pole to 7 pole adapter or this this even fancier one?

What has me confused in my pop-up camper just has the 4 pin connector on it. My Durango had a 7 pole connector so I always used one of these 7 pole to 4 pole connectors.

But, it would appear that I need to go 4 pole to 7 pole on the tow rig end and then back from 7 pole to 4 pole on the trailer side

Maybe there is some whizbang stuff going on in the adapters that allows the trailer brake connection to function?

I need to tackle this this weekend so any help will be MUCH appreciated. If I have to I will just redo the whole dang thing, assuming I can find the needed parts locally.


P.S. Remaining items on my must do mod list are the trailer brake controller, sliders, CDL switch and Pin 7 mod (hopefully), CB, and adjust the e-brake . There are about 10 additional items on my want to do list. Should I start a poll on whether you all think I'll be ready in time

 

[Beater]

I was under the impression that you need a 7 pole or 6 pole to do brake controller, but I am sure Kev or Ige know the correct answer

 

[Romer]

I had to change the connector on my trailer harness for the popup to the bigger connecyor. I run surge brakes so I can't help you with the controller. What trailer are you running, curious if you need a controller for the load.

I would do the SDL and CB as first priority. You miss a lot on the runs without a CB.

Not sure when you are getting there, but could adjust the e-brake there if needed.

I still have not done the pin 7 mod. Haven't been in a situation where I wanted to use it. I know others love it.

 

[Uncle Ben]

I'll play but I am You state that you have a green wire coming from the battery, can I assume this is from the + side? If your trailer is only a 4 pin connector either someone has changed it or you don't have electric brakes. Trailer lights are often handled by three wires (brown, green, yellow). The forth wire will either be ground (most likely) or a charging wire for the camper battery. The first link of plugs is the most common type of trailer/brake connector. the 7 pins would be tail lights, left turn/left brake light, right turn/right brake light, ground, brake exciter, brake ground, and charging circuit.

 

[corsair23]

I had to change the connector on my trailer harness for the popup to the bigger connecyor. I run surge brakes so I can't help you with the controller. What trailer are you running, curious if you need a controller for the load.

I would do the SDL and CB as first priority. You miss a lot on the runs without a CB.

Not sure when you are getting there, but could adjust the e-brake there if needed.

I still have not done the pin 7 mod. Haven't been in a situation where I wanted to use it. I know others love it.

Ken,

Thanks for the insight. The trailer is a coleman popup, probably in the 3500# range give or take. Probably not an absolute must have to have the trailer brakes working other than the additional safety factor etc. The wiring it relatively easy and shouldn't take too long once I figure out what I need to do

As for my ebrak adjustment. I may have to take you up on the offer. I tried the test to hold the vehicle in drive @ 1200 rpm with the ebrake on and it was iffy. The ebrake on the 80 holds nice and tight with about a 45 degree angle on the handle, on the LX I have to pull the handle ALL the way up.

 

[corsair23]

I'll play but I am You state that you have a green wire coming from the battery, can I assume this is from the + side? If your trailer is only a 4 pin connector either someone has changed it or you don't have electric brakes. Trailer lights are often handled by three wires (brown, green, yellow). The forth wire will either be ground (most likely) or a charging wire for the camper battery. The first link of plugs is the most common type of trailer/brake connector. the 7 pins would be tail lights, left turn/left brake light, right turn/right brake light, ground, brake exciter, brake ground, and charging circuit.

UB...I should learn not to type questions late at night when I tired as I tend to confuse the issue

The green wire coming from the battery is coming from the positive side and runs back to the Draw-Tite Modulite Lite light power module referenced above. Apparently this little module takes power directly from the battery to the module to power the trailers lights (markers, stop, turn, etc.) rather than adding the additional load to the vehicle's lights themselves. Several advantages of this per the link referenced, one of them being able to avoid having to upgrade to a heavier duty flasher unit.

I'll have to reconfirm what the trailer has (it is stored at the in-laws) connector wise but I could have swore it was a 4 pin as I believe I always had to have my 4 pin to 7 pin adapter with me to hook up to the Durango. But, it has been a couple years since I was the one actually towing the camper since the Brother in-law bought a Silverado. What I do know is it has brakes that can be controlled via the brake controller as it worked like a champ when I had the brake controller on the Durango.

 

[farnhamstj]

Edit your must do to Trailer, Sliders, CB, parking brake.

 

[Beater]

dude - no 80 ebrake holds at rpm... none that I have driven. I just adjusted the crap out of mine, the ebrakes themselves are good, and it's shite

 

[corsair23]

Ok...talked to the brother in-law and the connector on the popup has been converted from the 4 pole to the 7 pole connector...He did this when he got his Silverado and I haven't towed it since

So, tomorrow I'll be on the hunt for a 7 pole adapter/connector and associated wiring to wire up my brake controller and convert my existing 4 pole connector to a 7 pole connector

Shouldn't take me more that 3 or 4 days to get that all wired up

Ok, seriously should take me longer to find all the piece parts than wire everthing up...

Now, to get Romer over to install me a subtank and life will be golden

 

[Romer]

Go to an RV store and they will sell you an adapter

 

[Uncle Ben]

helpful site on connectors
this might lessen the head scratching a tini bit.....