After market 7 pin ground wire keeps blowing fuse

[stefanarroyo]

Thank you for all your help.
What we ended up doing is;
We left the campground early today, and thankfully today is a holiday up here in Canada so traffic was very light. We took it slow in the right lane and kept a safe distance to avoid having to brake much. But our trailer brakes worked well just no lights.
I know it's not safe and not ideal or legal lol, but had to get home somehow.
Now I can take the time to take it in and say what gives here ? Haha
Thanks for all your help, and trying to work through it with me

[curls]

I would strongly suggest taking it back to the shop that installed it originally.
I installed my own wiring last year (the week after Victoria Day) and this past week I had to deal with a corroded ground pin on my vehicle-side 7-way socket, and after changing that, I found that the Curt T-harness (converts brake light signal to a powered brake/turn/running lights for trailer) is also toast. That part is being ordered and should be a simple swap/plug-n-play.
My trailer brakes work but I also had no lights. UGH!

I have a fair bit of 12 volt electrical knowledge, and installed the entire thing myself, and it's still a PAIN to troubleshoot.

[stefanarroyo]

I have made an appointment for this Thursday. He said the wiring has a manufacturer's warranty of 1 year. I exceeded the 1 year mark last month. But he said running a new wire from 7 pin receptacle to battery and swapping out the old is easy and he said it wont be much and they'll help me out. I'll provide an update

[Johnynorthland]

Just a thought. I don’t know how comfortable you are doing this but; Go to the store by a small spool of automotive wire to use as a jumper (temporarily). And some crimp On connectors. Cut and splice in the new wire just before the fuse on the battery than cut and splice it on your trailer connector. See if that blows the fuse. You could probably tuck it under your hood through the driver and passenger doors , your trunk etc..into you connector and drive that way until you finally get it fixed. Just don't pinch or expose the wire and cause another short.

Good luck let us all know how you resolved it.

[Wireman]

Originally Posted by Will P

You said,"Just shy of the battery terminal in the car, there is a curt ground wire that attaches to the battery and it has a mini fuse box just before the terminal." That doesn't sound right. I've never seen a fuse in a ground wire. My guess is that that is the positive wire that supplies power to the trailer all the time you are connected. Did you do the wiring installation yourself? And Did the set up always work and now suddenly this problem started to happen?

X2 Never seen a fuse on the negative side. You have a short to ground in the 12 volt side somewhere.

I'd sure ask why there is a fuse on the negative side of the wiring.

[stefanarroyo]

Sorry if there was some confusion. The wire with the fuse was attached to the POSITIVE side of the battery.
I took the van in to get looked at by the place that installed it.... sure enough, the 12v wire was rubbing somewhere under the vehicle and rubbed through the insulation causing the short. They fixed that wire for me for no charge which was great.
Except when he said that all your lights work now except your running / tail lights . Since I replaced the 7 pin receptacle last weekend myself, he said to recheck my wiring job on the receptacle... but it's right.

He also said his reader was showing up as a ground error that's causing the running lights not to work. He said the wires from the receptacle go to a harness tie in box somewhere along the vehicle and those boxes sometimes fail causing some lights not to work. Anyone know what hes talking about?

[norty1]

Not clear how a box fails? It should just be a junction box. Maybe he means a wire is grounded in the box?

[berwin]

I'm no expert but why couldn't you just attach the ground wire to your frame instead of running it all the way up to the battery?

[curls]

Use a multimeter to check the 4-flat coming out of the tie-in harness - it'll be upstream of your 7-way. Check that you have nearly 12 volts coming from brown and grounded to white, with van lights on. Check for near 12 volt on green/white and the yellow/white with vehicle brakes applied. Lastly, check that yellow/white alternates from 0-12 volts with Left signal on, and green/white alternates 0-12 volts with Right signal on.
If all of these pass, your connections downstream of the 4-flat are messed up somewhere (likely at the 7-pin socket - be aware there's a difference between 7-way blade TRADITIONAL and 7-way blade STANDARD wiring... it's so dumb!
If any of these fail, check for an under-hood FACTORY fuse for "Trailer". As an example, I eventually found my Santa Fe has a 30A fuse for the trailer wiring power output. The Curt T-harness which converts vehicle signals to a flat-4 output, requires the power from this fuse to work... so I was getting signals in to the t-harness, but there was nothing coming out! I changed the fuse (blown previously when the old harness box shorted internally - corrosion) and things all work perfectly again.

[stefanarroyo]

I did some trouble shooting this weekend with my father in law who knows how all these things work.
We were able to take off some paneling near the back of the car and found the curt converter box. All the pins work except the brown running lights pin. There was no power coming to the receptacle on the bumper through the running lights brown wire. Followed wire to the box, and tested that were IS power coming to the box from the brown wire, but no power coming out of the box. We concluded that there is something going on inside the box with the brown wire that's not providing any output.
Also, the box is completely sealed and the inside cant be accessed.

I've reached out to curt to see if they have any suggestions or what they can do for me about this box before I go buy a new one.
But thankfully my EB, RT, LT, BL all work

[curls]

When you do replace the box, get a can of Leak-Seal spray (the stuff that makes your screen door into a boat! LOL).
My CURT dealer told me that this was something he recommends to all customers recently after a bunch of these "sealed" boxes are failing. Water is getting in somehow!

I sprayed my replacement one with 2 coats especially around the area the wires enter it - it looks to be even more water-tight than before.

[stefanarroyo]

I will do that! Thank you very much for the advice!