No running lights

[Jake930]

We are on a trip and my running lights on the trailer quit working. Got brake lights and blinkers but no running lights. Any ideas?
We will be off the road before dark anyways, so no problem with that. Just wondering if their maybe a Quick fix.

[davidmurphy02]

I have had an intermittent problem with that - apparently an intermittent short in the wiring in my truck. Sometimes the running lights work, sometimes not, have never been able to get it successfully diagnosed. You can pick up an inexpensive testing plug to put in the 7-pin connector on your vehicle and determine for sure whether the problem is in your truck or trailer wiring. https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

I almost never drive at night, on the rare occasions where it's been dark and stormy during the day I just put on my emergency flashers so the trailer is clearly visible to anyone coming up behind me.

[Ron in BC]

I actually carry a set of boat trailer magnetic lights for this situation. Yah, probably guarantees that I'll never have this problem. But we often are on the road at night so I consider them cheap insurance.

Ron

[cpaharley2008]

Ron,
Could you please post a link to the item "boat trailer magnetic light" you mention, maybe something to consider. Thanks

[Ron in BC]

Similar to these, although Amazon seems expensive since similar ones are on sale at Princess Auto, our Tractor Supply, for 20 bucks CDN.

https://www.amazon.ca/CZC-AUTO-Magne...g=askmenosp-20

The only time in recent memory that I didn't carry a set with me was when I went out to ETI to pick up the 21. We duly checked the lights before pulling out of their parking lot. No brake lights. ETI brought their tester out and the trailer lights were fine. Our truck was the problem. So a couple of mile drive to the dealer in an area of heavy traffic. I faked brake lights. Every time I slowed down I'd flash my running lights which had the same effect. Turns out a truck fuse had blown, complete mystery because the lights have worked flawlessly since. Touch wood.

Ron

[bborzell]

Does your TV have an “Auto” lights setting? Mine does and I have to turn the switch to “On” to get power to the running lights.

[rubicon327]

Originally Posted by Jake930

We are on a trip and my running lights on the trailer quit working. Got brake lights and blinkers but no running lights. Any ideas?
We will be off the road before dark anyways, so no problem with that. Just wondering if their maybe a Quick fix.

A quick thing to check is your 7 pin connector on the truck. I’ve had the standing tabs compress and create an issue. You can bend them back out with a small flat blade screwdriver.

[HABBERDABBER]

Originally Posted by rubicon327

A quick thing to check is your 7 pin connector on the truck. I’ve had the standing tabs compress and create an issue. You can bend them back out with a small flat blade screwdriver.

I just did this repair action last trip to fix a wonky connection to the brake controller.

[Ron in BC]

Originally Posted by bborzell

Does your TV have an “Auto” lights setting? Mine does and I have to turn the switch to “On” to get power to the running lights.

Interesting, it must vary by brand. My F150 has "Auto" for the headlights and the trailer running lights come on when the truck lights come on.

Ron

[BruceW]

Just to be sure that it isn’t just the light switch not being in the right position, check each of these usual positions:
AUTO - only comes on when it’s dark or close to it.
RUNNING LIGHTS ONLY - This should turn your running lights on
ALL ON - This should turn your running lights on, too, along with headlights.
If the last two don’t work then it’s probably a tow vehicle issue, connector problem or perhaps the brake controller if everything runs through it.
Good hunting!

[Brian B-P]

The brake light and signals ("blinkers") use the same wires and lights - so those are working. All lighting functions share the same negative (ground) connection to the tow vehicle, so that must be working, too.

By "running lights" I assume that you mean both tail lights and marker/clearance lights. If some of those are working and others are not, it is bad connections or failed lamps within the trailer; if they're all not working, then the problem is in the circuit consisting of the single wire from the tow vehicle, single contact set in the 7-pin connector, single wire from that contact, or the wires attached to it. The usual troubleshooting method is to start somewhere that's easy to reach (the 7-pin socket on the tow vehicle): if it doesn't work there then follow the circuit forward from there to where it starts working; if it does work there then follow the circuit back from there to where it stops working.

[Brian B-P]

Originally Posted by BruceW

... If the last two don’t work then it’s probably a tow vehicle issue, connector problem or perhaps the brake controller if everything runs through it.

The running light circuit won't run through a brake controller... just the brake light circuit.

[Jason]

Originally Posted by Jake930

We are on a trip and my running lights on the trailer quit working. Got brake lights and blinkers but no running lights. Any ideas?
We will be off the road before dark anyways, so no problem with that. Just wondering if their maybe a Quick fix.

Your brake lights and your turn signals are on one fuse in your truck and you have a separate fuse for your running lights for the trailer it is probably that, check your truck manual for where to locate that fuse.