re-wiring my 7pin

[davelinde]

So... dummy me didn't listen to DW who was saying "I don't think you are disconnected"... last time I pulled away from my RV and I yanked my 7 pin cord clean off my trailer. (as I KNEW... I had disconnected the cord - but it was caught on the truck as DW was trying to tell me)

My RV has a junction box so I just need to reconnect the wires AND I have the color coding of the wires on the cord side. I need to ask if I figured out the brakes correctly though. Brakes are blue... but I've got 4 blue wires!?

One is from the truck, that makes sense.
One comes from the emergency brake switch, that makes sense.
But there are TWO blue going back towards the brakes? why?

From the way it all pulled apart during my incident it LOOKS like the emergency brake is connected to one of he blues (I think I know which it was) and the truck connects to a different one? Is that right?

Why are there two going back? Why aren't they all just tied together?

 

[jnbhobe]

There may be one for each side. My Bighorn crossed thru the axel not sure about Cyclone. One side of the breakaway should be hot(12V) the other side goes to the brakes.

 

[davelinde]

There may be one for each side. My Bighorn crossed thru the axel not sure about Cyclone. One side of the breakaway should be hot(12V) the other side goes to the brakes.

Right, yes I'm sure about some of this. The power lead up to the switch did not pull apart and is still attached, the switched power (brake-blue) comes back from the switch and was also still attached to a blue wire (but loose now). There is a SECOND blue leaving the box.

My first thought was that (for a reason I didn't understand) the brake wiring was parallel - one for emergency and one for the truck control. Now I'm thinking you are probably right and that before I yanked it all 4 blue wires were joined, and when I yanked it out, two stayed connected and two came apart. Now I'm trying to remember how many crimp connectors I found in there... that would help me figure it out.

 

[2010augusta]

from the wiki:

//heartlandowners.org/mediawiki/index.php?title=7-Pin_Harness
//heartlandowners.org/mediawiki/images/thumb/4/4e/Harness.JPG/884px-Harness.JPG

one of the four blue wires is un-used.

 

[jnbhobe]

Alan where does the extra blue wire go to?? I know the yellow is Backup lights. Just wondering about the extra blue one.

 

[2010augusta]

Alan where does the extra blue wire go to?? I know the yellow is Backup lights. Just wondering about the extra blue one.

Jon, I am not sure, but according to the diagram the brake system has its own Romex that is a supplement to the 7-wire harness on the trailer. It could be that the Romex is a different/better wire for brakes than what is in the other 7 wire bundle.

 

[davelinde]

just on my way to start connecting it up. saw this and thought YEAH we have a WIKI (who knew...)
Read the WIKI and not I'm more confused... looks like some plug and test is in order.

 

[davelinde]

plug and test worked and the wiki is right for the colors on the RV side.
I had a new 7 pin cable with different colors but the documentation on that one was right so I matched them all up first shot.

I can confirm the second blue (the wire NOT in the extra romex like jacket) is not a brake line. My controller reads "NC" connected to that but connected to the other one showed a connection right away.

Hopefully good to go now.

 

[irvin56]

Someone needs to buy Alan a few tanks of fuel for his wisdom and info he has posted and submitted to this forum and wiki.
Great info and work there Sir.

Hint to JB. and heartland

"I am trying Alan"

 

[loafer]

Yes, Alan has wisdom beyond his years and is a definite asset to this site. Guess its his school teaching background LOL
Thx for all your help it is Alans and lots of others here that make this the best Rv site on the net.
Keep up the good work folks
Just MHO.
Bill

 

[2010augusta]

Thanks guys,

Just remember that before I was a teacher, I studied Mechanical Engineering, designed race-cars, built Jeeps and out buildings, and have remodeled houses. Dad had me out in the garage while I was still in diapers. some of my first "toys" was a set of real tools. Jack of all trades seems to fit me well.

I am glad that ya'll find my knowledge helpful, but I still learn more everyday from this forum too.

 

[irvin56]

How old are you

Young man. holy. must be nifty fifty

 

[2010augusta]

How old are you

Young man. holy. must be nifty fifty

I just turned 29 in June