Toyota Tundra Forums banner

1 - 10 of 10 Posts

·
Registered
Joined
·
57 Posts
Discussion Starter #1
Just wondering if anybody else is having trouble with blowing the fuse for the tail lights on the trailer wiring connector. On my 08 DC I have blown the fuse twice in the last few weeks. This is not a little blade fuse. It is in the fuse box under the hood and one of the large square ones that protects only the tail lights of the trailer. It hasn't blown while towing its just been blown when I first hooked onto the trailer. The dealer suggested a short on the trailer. Not so. It hasn't blown when towing with my other truck. This is not good when I go out in the dark for a trip and find I have no trailer tail lights. Any input?
 

·
Premium Member
Joined
·
5,467 Posts
If you are blowing the 30 amp fuse there has to be a short somewhere. The only thing supplied from that fuse is the trailer tail lights. If it's blowing when you first plug it in check your connectors. Here's a link to the wiring diagram.
trailer-towing.pdf
 

·
Registered
Joined
·
2,966 Posts
I just went thru this same thing this morning, my fuse under the hood blew (30 amp) and my running lights on the trailer went out. Check and see, but you should still have turn and brake lights, just no running lights. You have a short in you running lights somewhere (brown wire).

Start at the tongue and look for the brown wire being pinched or exposed and touching bare metal. Slide under the trailer and keep looking for the damaged wire. If you have front running lights as well, you can easily narrow your search by cutting the wire at the rear of the trailer, if your front running lights come on, your short is somewhere in the rear.
 

·
Registered
Joined
·
2,966 Posts
If that will have an effect I will give it a try. My lights are always on during the hook-up leaving pre-dawn for trips. Thanks
The headlights being on or off should have nothing to do with your problem. You have to find the short.
 

·
Registered
Joined
·
3,058 Posts
The headlights being on or off should have nothing to do with your problem. You have to find the short.
If there was a short in the trailer, there would be issues hooking it up to other vehicles. The OP stated that there are no problems pulling that trailer with a different truck. I have seen several instances of the fuse blowing when you plug the cord in with the lights on. Just a few months ago an RV was in the shop because itnwas blowing the fuse when plugging in his tow car. I was unable to find any problems, so I had him come out and show me how he does it. I learned he plugs the car in with the RV lights and 4 ways on. I told him to turn the lights off before plugging it in and there have been no issues since. I have also had it happen on personal vehicles.
 

·
Registered
Joined
·
7,461 Posts
i plug mine in all the time with the lights on...but then again my boat trailer is all LED and doesnt draw much of anything.

OP, you say your trailer works fine on another vehicle...still might have a short that the other vehicle isnt fused for and its just overheating wiring....

have you tried hooking up another trailer to your truck? if its when u just plug it in unless u have the hazards or turn signals on then it has to be in the running light circuit as stated above. cant be in the turn or brake circuits if they arent on. but i agree, plugging them in when on "shouldnt" have anything to do with it but give it a try, you might just have a trailer with a bazillion lights on it that draws too much when plugged in...if thats the case, the fuse will blow when u turn them on....plugging them in or unplugging them when on shoudnt be any different than acting as a switch and a switch certainly wont blow a fuse...so look at the trailer closer...
 

·
Registered
Joined
·
57 Posts
Discussion Starter #10
Thanks for all the advice. It makes me think short in the wiring. All LED lights so its not a big draw. The thing has done it twice with about 8 wks apart. The part that stumps me is it has not done it when actually towing. Some investigation required.
 
1 - 10 of 10 Posts
Top