No Trailer Running Lights (have brakes and flashers)

[MtAiryEd]

Hi, All.

I have a 2013 4Runner SR5. I tow a small boat. I lost my running lights last trip and drove home with the flashers on.

The flashers, breaks, and turn signals work. I use the four-pin connector.

I have found that the brown wire is for the running lights. I first checked the continuity in the trailer, and that was fine. I then found I do not have power at the prong/pin at the vehicle that feeds the brown plug/wire on the trailer plug.

I checked for fuses. Under the hood there are two related items...one is the relay "Towing Tail" and the other is a 30A for towing. That one is fine, but that would seem like a general towing fuse, and not specifically for the running lights alone.

I can take it in under warranty, but I thought this would be a quick, at-home fix.

Any clues?

THANKS!!!!

 

[4Runner4TW]

I actually having the same issue on my 99, I'll be watching this threat. hopefully someone will chime in!

 

[Kraze]

I don't know about the 5th gens, but on the 3rd gens, there's a splitter box in the drivers side panel back in the cargo area that I guess fails all the time and you'll lose one set of your trailer lights. That's where I would check first. I had to replace mine due to that same problem.

 

[philsey]

Do your headlights need to be turned on?

 

[NuclearN8]

I know this is an old post but I have the same issue as [MENTION=98932]MtAiryEd[/MENTION]

on my 4runner all the trailer lights works except no running lights. my wife's 07 4runner everything works as it should so I know it's not the trailer or 7 to 4flat and extension I use.

Any ideas from anyone else on this issue?

thinking of buying one of these to see if it fixes the issue since it's plug n play
https://www.etrailer.com/Custom-Fit...unner/2005/HM43374.html?vehicleid=20051230091

 

[MtAiryEd]

My dealer found a newly added fuze that solved this issue.

 

[Raven]

Relay

I had exactly the same problem with my FJ - new trailer, everything worked fine except running lights. No problems found anywhere in the wiring circuit.
Discovered "Trailer Tail" relay was missing, even 'though I had the towing package. Couldn't locate a relay right away, so simply stuck a short jumper wire between the contacts, and voila ..... lights!

That relay only controls the trailer tail lights! (and, it ain't cheap!)

 

[ebg18t]

I know this is an old post but I have the same issue as [MENTION=98932]MtAiryEd[/MENTION]

on my 4runner all the trailer lights works except no running lights. my wife's 07 4runner everything works as it should so I know it's not the trailer or 7 to 4flat and extension I use.

Any ideas from anyone else on this issue?

thinking of buying one of these to see if it fixes the issue since it's plug n play
https://www.etrailer.com/Custom-Fit...unner/2005/HM43374.html?vehicleid=20051230091

It's worth a try. My first 7 to 5 flat adapter didn't work. But the 2nd one did.

 

[Jeff614]

I've had this happen on other vehicles. Always seemed to happen when I accidentally plugged the trailer harness in while the vehicle lights were on. Resulting in a blown fuse. Same thing would happen. Brake lights and turn signals work fine but no running lights.

Mostly occured in 3/4 and up trucks and it was one of the larger fuses (30 amp +) that blew. I'd bet it's the same cause with the 4Runner though. Easy to do when hooking up a trailer at night but was def the cause the two times it's happened to me.

Hope you get it straightened out!
- Jeff

 

[NuclearN8]

so the 2- towing related 30A fuses in the fusebox seem fine (swapped them with no change in condition)... I'm going to do some troubleshooting this weekend with a dmm and voltage light at all connection points but I think I'm leaning towards a faulty towing converter relay box.
I need to remove the left side plastic in the cargo area to gain access to this item to be sure before ordering a new one.
I'll report back what the cause was so maybe others who have the same issue can benefit from it.

 

[NuclearN8]

This issue for me was resolved by replacing the towing converter relay.
The towing tail relay (90987-02016), and towing fuses were good under the hood.
I replaced the towing converter relay (81985-35010) behind the left side rear cargo panel and now my trailer running lights work as the should. I will troubleshoot the converter relay this winter to try and figure out what part of it failed and update later

 

[kww]

fixed

2013 4Runner limited

so I plugged my trailer at night and pop. Running lights are a no go. So keep your truck off when hooking up your trailer. Under the hood 30 amp fuses for trailer lights blown. Replaced fuse and there working! Hope it helps

 

[smeier]

Trailer Lights

Had the same problem with no running lights but signals, hazards, and brakes worked. Hooked the trailer up to another truck and everything worked. Opened the fuse box and the 30 amp trailer fuse was blown. Replaced it and everything works. Must have either plugged the pigtail in or disconnected it with the vehicle powered up. Won't make that mistake again.

 

[Black2011]

My no running lights on trailer story.

Oh man. I have been using my 4 way Flashers for 2 years now. My last effort I took my bumper off and got in there to the pig tail with a test lights went thought it all. The 7 pin worked with runners until I hooked up the 4 pin. On and on until I got on here and someone (thank you) posted the fuse #34 30amp was the issue. I couldn’t believe it. I thought I checked them all.

Thanks !