Changed tongue jack, now trailer running lights don't work!

[TitanMike]

Originally Posted by Guspech750

My Jack has a black and white wire.

The white should then be connected to trailer frame ( usually at a jack mounting bolt) and black directly to battery through an inline fuse.

Some jacks already have the white wire connected internally.



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[Guspech750]

Originally Posted by TitanMike

The white should then be connected to trailer frame ( usually at a jack mounting bolt) and black directly to battery through an inline fuse.

Some jacks already have the white wire connected internally.



Sent from my SM-N950U1 using Forest River Forums mobile app

Yeah. I guess my post was a bit vague. LOLzzzz. My apologies. The white is grounded and the black is connected directly to the battery.

[jmschield22]

this is a great response. Thank you for this.

As mentioned, you are correct, for my model, forest river wildwood 22 rbs, i have a white and black wire, along with a black and white wire for the light.

THe concensus seems to be that those black and white wires have absolutely nothing to do with the trailer lights, which leads me to believe that a fuse is blown in my truck.

I am a bit confused on how I can check the voltage on my 7 pin. How can I check to see if there is ampage on my 7 pin with my truck?
I should be able to tell right away if my truck is the issue with getting ampage to the 7 pin connector from the rv.

Thanks!

[jmschield22]

to add onto my last response.

IF it is a truck issue, why would my brake and turn signal lights work and not my trailer running lights?

[Cruzrtwdgt]

Originally Posted by jmschield22

to add onto this, why would my brake lights and turn signal lights work, however, my running lights don't work?

Different circuit, different filament in the bulbs (or separate led). I'd get a meter, connect to truck, turn on lights and start checking inside the trailer light connection box up front. It may just be an issue separate from your hitch repair.

[Aussieguy]

Originally Posted by jmschield22

this is a great response. Thank you for this.

As mentioned, you are correct, for my model, forest river wildwood 22 rbs, i have a white and black wire, along with a black and white wire for the light.

THe concensus seems to be that those black and white wires have absolutely nothing to do with the trailer lights, which leads me to believe that a fuse is blown in my truck.

I am a bit confused on how I can check the voltage on my 7 pin. How can I check to see if there is ampage on my 7 pin with my truck?
I should be able to tell right away if my truck is the issue with getting ampage to the 7 pin connector from the rv.

Thanks!

using a multi meter is not hard.
once you learn the basics ... you will find it is the tool you grab first because it eliminates the guess work.
https://www.google.com/search?client...ruck+connector


If you get stuck on testing a particular item you can google it

how to test xxxxxxxx with multi meter
xxxxxxxx = replace with name of item suspected as broken!


there are some tutorial sticky on using multimeter somewhere on this forum
WMTIRE knows where they are!

[dannyabear]

There is nothing wrong with your truck or fuses; the jack is not grounded to the trailer frame even tho you have 3 bolts attaching it; remove the bolts one at a time and remove the powder coating from the jack so that you get metal to metal contact...

[Mr. Dan]

Originally Posted by dannyabear

There is nothing wrong with your truck or fuses; the jack is not grounded to the trailer frame even tho you have 3 bolts attaching it; remove the bolts one at a time and remove the powder coating from the jack so that you get metal to metal contact...

He doesn’t seem to be having any problems with his jack so there’s no need to fool with its ground. It’s some of his trailer’s lights that aren’t working.

[jmschield22]

the bolts are connected to the frame. I can check but there is not powder coating that i remember. Also that wouldn't explain why just my brake and turn signal lights work and the running lights dont work.

[IamProStreet]

If you do the fuse trick I recommend you will narrow down the problem. If the lights work the problem is in the truck, if they don’t then the problem is with the trailer. I’m a ASE master automobile technician and know how to diagnose problems. You have to start by knowing for sure what system the problem is in. Unless you pinched a wire by installing the jack changing the jack out will not affect the lights, two unrelated systems.

[Mr. Dan]

Originally Posted by IamProStreet

If you do the fuse trick I recommend you will narrow down the problem. If the lights work the problem is in the truck, if they don’t then the problem is with the trailer. I’m a ASE master automobile technician and know how to diagnose problems. You have to start by knowing for sure what system the problem is in. Unless you pinched a wire by installing the jack changing the jack out will not affect the lights, two unrelated systems.

X2
Every time I've had an issue like this, I've found a blown 10amp micro/mini? fuse burned out in my truck itself... sometimes with no rational connection to recent activities. A service center worked on my trailer. When I picked it up, one light on the rear of the trailer didn't work. A service center employee went inside, grabbed a couple of 10a fuses, found and replaced the bad one and all was well.

[Cb25 Joe]

Google 7 pin light tester. Just plug it in and it will show you what lights are working on your truck.

[Bob K4TAX]

There are 7-pin testers available at auto parts stores. They have a series of lights or LEDs when plugged into the truck connector will allow one to see what circuits are active. Of course, you will need to have someone assist you with pushing the brake pedal, turning on and off lights, and turn signals.

As to testing the trailer, you can use a jumper connected to pin 4 which is the 12V on the trailer. DO NOT JUMP THIS TO PIN #1. A jumper from pin 4 to each of the other pins, one at a time individually, you can observe the lights in each location. This will let you know what is working and what is not.

Bob

[Aussieguy]

yeahh jump the ground at your peril.


better to learn the multi meter method then you can use it around the hose.

AND jumping 120v... much more frowned upon.
The arc is so nice and blue... DON"T ASK

[Larry-NC]

Originally Posted by Bob K4TAX

There are 7-pin testers available at auto parts stores. They have a series of lights or LEDs when plugged into the truck connector will allow one to see what circuits are active. Of course, you will need to have someone assist you with pushing the brake pedal, turning on and off lights, and turn signals.

As to testing the trailer, you can use a jumper connected to pin 4 which is the 12V on the trailer. DO NOT JUMP THIS TO PIN #1. A jumper from pin 4 to each of the other pins, one at a time individually, you can observe the lights in each location. This will let you know what is working and what is not.

Bob

You can get a tester for the seven pin connector like these at Amazon, Walmart, eBay, Advance Auto, AutoZone, O'Reilly's, or even Pep Boys.

[sparky986]

Your truck will have a fuse under the hood, in the engine compartment, that is for trailer lights. If you had a wire spark it could have blown that fuse. If your brake lights work on the trailer, and turn signals, then it has to be running lights fuse.

[dedobias]

Let's get even more simpple. The two problems may be unrelated. If you look at the plug picture with the fuse, notice each hole has two brass tangs and many of them are NOT touching in center which means they have been bent back over time. Tanke a small screwdriver and bend both in each hole toward the center until they touch. It may just be a bad connection

[Larry-NC]

Originally Posted by sparky986

Your truck will have a fuse under the hood, in the engine compartment, that is for trailer lights. If you had a wire spark it could have blown that fuse. If your brake lights work on the trailer, and turn signals, then it has to be running lights fuse.

Car/truck manuals these days are hundreds of pages long. Only nerds like me read them cover to cover.

But if you DO look in the index for "fuse", you will find two things:
One is listings of all fuses. As you read the listings, you will see two listings for items like brake lights, turn signal lights, and running lights. One of them will be marked TRL or AUX (trailer or auxiliary). Those are the fuses for the plug that the trailer plugs into. Find the fuse you are looking for, maybe "Running lights TRL."

The listing will give a reference to which fuse panel and it is (under hood, left dashboard, or right dashboard), and a number. Look in the manual again, and for each panel, there will be a map--a drawing of the fuse panel with the fuses numbered. Find the suspect fuse and pull it out (small pliers is helpful) and look to see if the internal wire is complete or has an open spot in the middle. Not rocket science and easier to do for yourself than to pay someone $25 to do it for you.

[bikendan]

Originally Posted by Larry-NC

Car/truck manuals these days are hundreds of pages long. Only nerds like me read them cover to cover.

Count me as a fellow nerd![emoji851]

[gw1800]

The tongue jack should work all the time even without truck being connected to the truck, or the trailer disconnect turned off.

The power wire for the jack is connected 'directly' to the battery. It may be connected at the thermal circuit breaker terminals on the trailer tongue.


Sounds as though someone replaced the tongue jack previously and did some wiring changes.