OK guys.... got an older 93 D350, that has two 6 prong plugs in it, one in the rear bumper and one in the bed wall. The wiring to them was cracked and rotted, so I cut it all out and installed one of the Hoppe wiring kits that plug into the factory harness. hooked it all up and everything worked great. Hooked up to the trailer nd checked everything , it all worked good.
Unhooked from the trailer and pulled into the garage, and BOOM, no right rear turn signal(left works fine), back up lights are coming on when I step in the brakes, brake controller is staying charged as if the trailer were hooked up, and have a weak current to the back-up lights when parking lights are on. if I unplug the Hoppe wring harness, everything works fine again.
I have good ground to the truck bed from the trailer wiring, checked all my splices and connectors, cant find a "bleed over" on any of them.....

any ideas?? this is driving me nuts!

 

sounds like you have the trailer brake and back up light crossed. double check all connections again. otherwise you would not have a brake light and backup light on togather hope it helps

 

I have said this time over and again, TRAILER LIGHTS should not be wired into the truck light system.

The only trailer lights that should get power from the truck system are the brake-lights/turn-signals.

Run a fused dedicated big wire from the hot battery terminal, through a BIG toggle switch, through the TM(trailer marker) terminal of the trailer-plug, and to the trailer marker lights.

With a good ground, this simple fix will eliminate all your trailer marker light worries.

Those aftermarket trailer-light harnesses are designed for light-duty service on trailers with only a couple of bulbs in the system.

They won't cut it on a big gooseneck, covered with lights.

 

I checked this... the Hoppe "kit" has four wires, Blue=brakes lights; Brown=running lights; yellow=left turn/stop;green=right turn/stop. The kit originaly had a 4-pin flat connector, I cut this off and fed the wires directly into the plug, then spliced my blue wire from the brake controller into the blue brake wire from the Hoppe harness. Ran a 12 gauge black from the plug to the frame as a ground. Have nothing going to the aux center pin.

My only thought is that I should have not used the brake wire in the Hoppe harness....but it should not be energized unless I step on teh brakes...
Brake controller is staying energized whethre lights are on or not..

Could my ground simply be bad?

 

BK, how do you wire for your stop/turn/brake control then?

My Gn only has 3 running lights per side, so i dont think using the Hoppe harness will hurt any....

 

disconnect the blue wire ,check operation the blue wire is used for trailer brakes not brake lights

 

normally the four pin flat is lt st/turn,rtst/turn,runninglts and ground , no brake light wire
1=yel -lt s/t
2=gr-rt s/t
3=br- run/lt
4=white-ground
if there is a blue instead of white it is probally a ground which is why you have what seems like a bleed thru

 

hmmmm. maybe I assumed( bad practice) that Hoppe would follow the "standard" .. better run out and check that.. I Am sure it is a ground problem, so that would make sense!

 

Nope, they had a seperate ground( white) at teh 4pin plug...Next idea?
I havea diagram of my wiring pending aproval so i can put it in here... maybe that will help

 

are you using the hoppy harness or the hoppy isolator. i put a hoppy isolator on my 92 w250. works great but the installation was interesting because of their choice of wire colors did not match the dodge, had to sort it out.
Clark

 

ok, went out and unhooked every connection, got the truck lights working, put the Hoppe connectors back in and tested them each for function......
The blue in the HOPPE's harness was nothing but back up lights!!!
There's a dern ASE color-code for trailer wiring, and that AINT it!!!!! I am madder than a wet hen! You'd think a company that makes all these trailer accessorys would follow the industry standards!!!

First I feel stupid for not checking this way first, and second I am PO'd that they used that color... and why in teh blazes would a four-pin flat need a back-up light wire>????? never hauled a trailer with that small a plug on it, but I cant imagine they have reverse lights........



steaminganddirtyandreadytocuss...................C D

 

I have a 6 way round or 5.....it's the small round. I think you would be better getting rid of the 4 flat and putting on the small round. This round has a dedicated spot for the trailer brake wire....like the blue one you said you had connected to brake lights I believe. If you stick with the 4 flat you'll have to rig up some stuff to connect your trailer brakes. I went with the small round cause that's what most everything is that I have used, made an adapter from the small round to the 4 flat for other trailers.

Now, what you said here,

"I checked this... the Hoppe "kit" has four wires, Blue=brakes lights; Brown=running lights; yellow=left turn/stop;green=right"

What did you hook the blue wire to actually? because I have seen the wires on the trailer stuff and they are brown, yellow, green and white. So did you put the blue on the white wire? If so when you tapped the brakes you shorted everything on that circuit to ground.

I'd wire in the small round and then retry, if that don't help check for fried wires and such or maybe you roached the brake box?

 

I run the electric brake wire directly from the controller to the S(supply) terminal in the plug, completely independent of any truck wiring.

I tap left and right turn power as close to the source as possible, meaning as close to the signal switch as possible; this gives turn signals and brake lights.

If you tie into the little bitty factory wires, way back somewhere under the bed, then there is a significant voltage drop on account of the smallness of the factory wiring.

Tapping into factory wiring is the primary cause of most trailer wiring woes.

The factory wiring is barely sufficient to support the truck itself, let alone a big trailer.

Also, big clean grounds can not be emphasized enough.

It is best to have a big seperate ground plug, seperate from the trailer plug, that is plugged, and un-plugged, just as the trailer plug, and securely grounded at both the truck frame and trailer frame.

Hope this helps.

 

OK, BK, I agree and hook mine up the same.. independant wire for Brakes from controller to plug, and I use the Hoppe connectors so as NOT to have to tap into the tiny factory wires. I use the wires from teh Hoppe connector for running, turn aux lights and I run a clean ground independantly of the trucks wiring harness.
This all goes into a 6 pin round connector that gets sealed with tape and heat shrink......normaly the blue wire in teh Hoppe connector kits will run your brake lights and flashers. It doesnt activate the brakes themselves if you use the center "AUX" pin for your brake controller.

Talked to Hoppe's customer service, and I have a defective part! There "blue" is suppossed to activate the trailers brake lights,Their connector"T" is not supposed to tap into the reverse lights at all.
I will be exchanging it at the parts store this afternoon.....

 

Standard procedure for a six-prong is S = Supply for trailer-brake.

If you wire trailer-brake to AUX, it won't work on someone else's trailer.

It will work fine on yours, though.