Need help wiring campers running lights

[BajaB]

I just replaced my old FWC that did not have running lights with a new one that does. When I plugged in my new camper, the running lights would not power on. I called FWC and they told me it was because my truck was not wired for running lights due to the fact my old camper did not have them.

My question is, how do I wire my truck/camper to power my campers running lights?

My truck is connected to my camper with the normal 3 prong Atwood trolling motor fittings.


Thanks!!

 

[Jack]

Your original wiring is just 2 wires, plus and minus, for charging. You need to run a third wire from your truck to the camper. Check with FWC, but the 3rd pin on the Atwood connector should be for your running lights line. On the truck side, your connect the new line to the fuse, using an adapter, for your trucks running lights.

Examples: https://www.amazon.com/Nilight-Circuit-Standard-Profile-Warranty/dp/B08QJHXRN6/ref=sr_1_3?dib=eyJ2IjoiMSJ9.zWZ7J6kP_PJmfHUOOjJCjdJ8TDLk4lfJ5XFyf7XjR1X2DHusW4_4qJ_l_GPExD9BkQjnoO5vmLh5KBhHY9tdA4aB5trKaRwd5AeT7MUO5b1KAcr9la13Ia5RN8BZVnnZ-ENXphRFUwop2J00NhYZJ6mnLnueK693fVwonZCvfGQih_5pgSfq-eMxi8JGOJOQECRGK0Nahg0_qP6VnlglxieL04niluIvDuPvnC7dm4o.pBBRT8mMpVdQ0LFHv2vL3XfhA0nBe1praTwo50zBg2A&dib_tag=se&keywords=fuse+connector&qid=1715295631&sr=8-3

16 gauge wire would be fine.

Does your truck have a smart alternator? If so, I suggest that you consider replacing the 10 AWG with 6 AWG wire. Not the best practice but you can splice your 6 WWG to the 10 AWG wire at the Atwood. As long as you have the 30A thermal fuse at the truck connection for the charge line, the Atwood connector and the 12AWG should handle the current. If your truck has a smart alternator and you want to charge from the truck's alternator, you will need a DC-DC Charger to get much charging out of your truck. Lots of post on this topic. My connector solution was bypass the Atwood to run the line over the top of the front of the truck bed to an Anderson connector accessed from the left front turnbuckle access opening. Easy to connect/disconnect and through a new hole into the camper I could run the 6 AWG directly to the DC-DC.

 

[Wandering Sagebrush]

Your Atwood should have power for charging, power for the clearance lights, and a ground. My guess is you may not have the running light circuit connected to the truck side. Check the truck connector with a multimeter. If you don’t have power on two of the pins when your lights are on, pull the Atwood out of the bed side and inspect it.

Warning: the charging circuit may be energized all the time. It’s easy to short the pins with the meter probes. Don’t ask how I know.

 

[dennis 221]

Does it not have that green wire to run to your rear lights?

 

[BajaB]

Thanks everyone. Sorry for the delay

As you guys guessed, the 3rd wire from my Atwood plug was not connected to anything in order to accommodate the running lights of my new camper (my old FWC didn’t have any).

So I figured the solution was simple. I used a 14 gauge wire and spliced it with the trailer running light power.

Except, still no power to my running light. Troubleshooting, I bypassed the trailer power source and ran the 14 AWG wire straight to a separate 12 volt battery. STILL NO POWER to my running lights!

I checked all the connections from the camper male end of the plug all the way to the fuse box. I checked the fuses,.. everything looks fine. Previous owner advised the running lights worked perfectly for him prior to the sale.

I’m at a total loss, what am I missing here? Any ideas?

Thanks!!

 

[PaulT]

Make sure you have connection between the truck negative supply to the camper negative supply.
Sounds like you have only half the needed circuit for the wires.
Because the truck running light is supplying the positive side thru the green wire, verify the the truck negative half connects to the camper negative half.

 

[BajaB]

Interesting, ok I’ll look into that. Thank you

When plugged in, my truck alternator is charging my camper. Would that still occur if it were not grounded properly?

 

[BajaB]

So I bypassed the truck with the separate battery using both the positive and negative from the battery. Still no power to the running lights.

I’m stumped

 

[Wandering Sagebrush]

A couple of thoughts… is there a camper side fuse or ckt breaker for the running lights? If so, have you put an ohm meter on it to ensure it’s got continuity?

If it’s good, do you have 12VDC on both sides? If you don’t, there’s a chance you have a broken wire or high resistance on the camper plug side.

If you do have power on both sides of the fuse, it has to be an open or high resistance on the lights side. My guess is at a (assumed) frame ground.

 

[Jon R]

What camper model and layout?

The factory wiring for recent model campers with running lights has an in-line fuse for the running lights, often located near the battery isolator. It looks exactly like the battery isolator fuse, and both have yellow wire. The fuse holder is a black rubber rectangular holder with a cap.

The grounds for the running lights are connected to the camper ground bus bars.