RV Trip Planning Discussions

Go Back   iRV2 Forums > TRAVEL TRAILER, 5th WHEEL & TRUCK CAMPER FORUMS > Trailer Towing and Tow Vehicles Discussion
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 11-08-2019, 09:42 AM   #1
Member
 
Join Date: Jul 2017
Posts: 33
Jeep Wrangler Light Wiring

We've been towing our Wrangler behind our motorhome as a flat tow for over a year now without a problem. We haven't moved it in a while, though, and since we are prepping for a big trip I wanted to check to make sure the lights work. Well, this time no luck.

I took out my trusty multimeter and ensured that I had voltage through the 7-pin connector on the back of the motorhome. So, it isn't the motorhome. I ensured I had voltage through the 7 to 4-pin converter as well. Then I tested the brown wire and ground coming out of the 4-pin connector going to the Jeep lights. Again, I had voltage.

I am not an electrical engineer, so I am assuming that I must have a short somewhere between the 4-pin and the lights. Is there a fuse in the Jeep that the wiring is usually linked to? Am I making a false assumption that voltage coming through the connectors means that the connectors are not at fault?

The lights on the Jeep work fine independent of the motorhome.

Any insights would be appreciated.
Thanks!
Bill
__________________

buzzbill is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 11-08-2019, 09:56 AM   #2
Senior Member
 
Ljwt330's Avatar
 
Join Date: Jan 2018
Location: Capistrano Beach, California
Posts: 1,174
Quote:
Originally Posted by buzzbill View Post
We've been towing our Wrangler behind our motorhome as a flat tow for over a year now without a problem. We haven't moved it in a while, though, and since we are prepping for a big trip I wanted to check to make sure the lights work. Well, this time no luck.

I took out my trusty multimeter and ensured that I had voltage through the 7-pin connector on the back of the motorhome. So, it isn't the motorhome. I ensured I had voltage through the 7 to 4-pin converter as well. Then I tested the brown wire and ground coming out of the 4-pin connector going to the Jeep lights. Again, I had voltage.

I am not an electrical engineer, so I am assuming that I must have a short somewhere between the 4-pin and the lights. Is there a fuse in the Jeep that the wiring is usually linked to? Am I making a false assumption that voltage coming through the connectors means that the connectors are not at fault?

The lights on the Jeep work fine independent of the motorhome.

Any insights would be appreciated.
Thanks!
Bill

Forgive me for not knowing the relationship between wire color and circuit, but I'll ask a few questions.


First, what, exactly, fails to work on the Jeep? We need to know that to help troubleshoot. Brown usually connects to the tail lights, but we need to know if that is the fault in your wiring.


Second, you tested the brown wire in the cord plug from the MH, but what about the other wires from the MH cord--the ones for the lights. brake/turn signals? Again, we need to know which circuits fail in the Jeep. If brown is for running lights, is that the only malfunction?


In my Wrangler, the wiring harness connections can be exposed after removing the left rear tail light assembly. You might check there to see if anything is amiss. Use your meter and check for power at the connectors behind the tail light assembly. Also, check to see if the harness of the Jeep is securely grounded--either close to the socket in front, or near the tail light.
__________________

__________________
Larry, Eileen, and Finley
2004 Alpine 36FDDS
Third motor home, first Alpine, no need for another.
Ljwt330 is offline   Reply With Quote
Old 11-08-2019, 10:13 AM   #3
Member
 
Join Date: Jul 2017
Posts: 33
Thanks for the quick reply!

To answer your questions, neither the brake, turn signals, nor running lights work on the Jeep when attached to the motorhome.

I suspected that the 4-pin was the problem, so I only tested the brown wire with the ground since my understanding was the the brown wire works the running lights and those are the easiest for me to check with the motorhome. I just checked the other two wires and both have voltage on the Jeep side of the 4 pin.

Thanks!!
buzzbill is offline   Reply With Quote
Old 11-08-2019, 11:03 AM   #4
Senior Member
 
Ljwt330's Avatar
 
Join Date: Jan 2018
Location: Capistrano Beach, California
Posts: 1,174
Quote:
Originally Posted by buzzbill View Post
Thanks for the quick reply!

To answer your questions, neither the brake, turn signals, nor running lights work on the Jeep when attached to the motorhome.

I suspected that the 4-pin was the problem, so I only tested the brown wire with the ground since my understanding was the the brown wire works the running lights and those are the easiest for me to check with the motorhome. I just checked the other two wires and both have voltage on the Jeep side of the 4 pin.

Thanks!!
Okay, if I understand you correctly there is voltage to all circuits at the end of the cord, but when plugged into the Jeep socket, you have no running lights, brake lights or turn lights. Is that right?


If so, my next step would be to look just behind the socket attached to the Jeep and see if there is any obvious problem, and follow the wires as far as you can easily see. If all looks good, remove the left rear tail light and expose the connections from the tow wiring. Test to see if there is voltage at each of the connectors from the 4-pin wiring to the Jeep's wiring. If no voltage, there is a break somewhere between the socket in the front and the connections at the rear. If there is voltage, there is a problem with the way the 4-pin wires were spliced into the Jeep's circuits.


Since your lights had worked in the past, I suspect something simple like the wires have somehow pulled out of the socket in the Jeep or the socket itself went "bad." Very easy to disassemble and/or replace if necessary.


Note, the above is how my Wrangler is wired which, I believe, is typical.
__________________
Larry, Eileen, and Finley
2004 Alpine 36FDDS
Third motor home, first Alpine, no need for another.
Ljwt330 is offline   Reply With Quote
Old 11-08-2019, 12:52 PM   #5
Senior Member
 
Ljwt330's Avatar
 
Join Date: Jan 2018
Location: Capistrano Beach, California
Posts: 1,174
One additional thought. Check the ground wire from the Jeep socket. If that wire is not grounded to the Jeep frame, power from the lighting wires will not "flow."
__________________
Larry, Eileen, and Finley
2004 Alpine 36FDDS
Third motor home, first Alpine, no need for another.
Ljwt330 is offline   Reply With Quote
Old 11-08-2019, 03:06 PM   #6
Member
 
Join Date: Jul 2017
Posts: 33
Thanks for all the ideas! I thought the ground was the issue and completely hooked up, but no joy. Checked the lights as suggested and nothing looks wrong. I am getting 13.4 V through the multimeter. My wiring setup has a diode. Could that have failed?
buzzbill is offline   Reply With Quote
Old 11-08-2019, 08:26 PM   #7
Member
 
Join Date: Jul 2017
Posts: 33
Thanks to your advice, I was able to track down the problem and correct it. It was, in fact, a flawed ground connection. Really appreciate the help! Cheers!
buzzbill is offline   Reply With Quote
Old 11-08-2019, 09:12 PM   #8
Senior Member
 
Ljwt330's Avatar
 
Join Date: Jan 2018
Location: Capistrano Beach, California
Posts: 1,174
Quote:
Originally Posted by buzzbill View Post
Thanks to your advice, I was able to track down the problem and correct it. It was, in fact, a flawed ground connection. Really appreciate the help! Cheers!
Glad I could help, and thanks for reporting the solution so others may learn.

Happy and safe travels
__________________

__________________
Larry, Eileen, and Finley
2004 Alpine 36FDDS
Third motor home, first Alpine, no need for another.
Ljwt330 is offline   Reply With Quote
Reply

Tags
light, wiring



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
2019 Jeep Wrangler Sahara Light Wiring K9sarsafety Toads and Motorhome Related Towing 4 05-14-2019 03:06 PM
Jeep Wrangler Rio Grande Edition :: 1995 Jeep Wrangler Rio Grande Edition Lindan n Jim iRV2 Owners Registry 0 05-27-2018 07:48 PM
While Towing a 2000 Jeep Wrangler, threw a Rod in Jeep Navion 24J Toads and Motorhome Related Towing 19 04-01-2017 05:33 PM
Jeep (JK) Wrangler MH to Jeep light wiring DEAL Coral Toads and Motorhome Related Towing 5 09-29-2016 02:26 PM
Jeep TJ Wrangler front diff gearlube burn Any Jeep towers present? CARVAL Motorsports Toads and Motorhome Related Towing 6 09-18-2011 10:22 PM

» Featured Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 03:05 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×