Trailer lights not working!?!?

I went to hook up my trailer today and noticed the lights were not turning on. So i checked all the fuses i could find and check all the harnesses, I also hard wired a normal flat plug to it with no luck. The trailer works on my friends truck so i know its not the trailer. Any Ideas?????

 

Did you check the fuses under the hood and under the dash?

 

if you check the fuses by removing them don't put them back in the wrong place like some other dumb ass has done.

 

I checked the fuses under the hood and dash, i put the fuses back in the right locations.

I dont have a multimeter but ill try to borrow one.

I think it maybe a short but wouldnt the lights at least flicker or somethin if it is a short?
Tracing those wires for a short is gonna be one hell of a PITA....

 

If the trailer lights work on your buddy's truck, then the trailer lights work - period. You ground through the ball. If you haven't had the trailer on for some time you may not be getting a good ground. Sometimes it takes a few blocks before you work off the rust in the coupler and on the ball before you ground out. You can also try and spray a little WD40 into the coupler. That's worked for me in the past.

Otherwise it's your truck harness that isn't jiving.

Hope this helps and good luck!

 

the trailer is supposed to ground through the harness thats what the odd prong is for on flat harnesses. Sometimes the ground becomes disconnected and the trailer grounds through the ball but its not designed like that.

 

my advice is grab a battery and test the light with direct power. Take your harness you used before and try to run the trailer of a battery. If they all work start at the back of the truck and work your way forward.

 

^^^Opps - my bad, I assumed the OP had a small utility trailer with the flat three pin connector that will use the trailer ball connection for ground between the trailer and tow vehicle.

 

No blown fuses...yet no lights. Do any of the trailer lights work at all? If not most likely a bad ground not a short. A short would blow a fuse. The number 1 terminal (white wire) of your 7 pin plug should be your ground, your hitch should not be your ground. A simple check with a 12 volt test lamp to the center pin (orange wire) or the # 4 terminal (black wire) should tell you if the truck is OK. If yes then check the trailer plug. But if the trailer works on your friends truck then it is most likely the ground on yours.
Good luck!

 

And just because it worked on your friend's truck and doesn't work on yours, that's no reason to assume it's your truck. Many people have had this problem (including me). Trailer worked on someone else's truck but didn't work on mine. It was a bad ground wire on the trailer! The trailer would ground through his ball, but not on mine giving the impression that something was wrong with my truck's wiring or fuses.

To start with the easiest possibility, just take a tester light and see if you have power going to the plug at the hitch using the above post. If you do, then it's likely the ground on the trailer. If you don't, then you've at least confirmed it's the truck.

 

Well said Moose, I should have been more specific and say to check the ground on the trailer plug if the truck tests OK. Thanks for making more sense of what I was trying to say!

 

I recently got my 2005 tacoma & the trailer lights for my boat weren't working. I too checked the fuses that were good in the cab & under the hood. I looked under the rear bumper to look at the wires & felt with my finger tips in the area around the corner of the back of the truck on the drivers side & inside the frame you can barely feel some fuses there. I just found 2 bad ones there. There are at least 3 there. Like I said you cant see them you have to feel for them. I checked it out with a volt meter & I now have the voltage for the trailer lights !!!

 

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Can you give more details as to where the fuses are? Pics?

 

bad ground........

 

Yup.

If none of the lights work, either a whole bunch of wires, bulbs, or fuses went bad all at once (not really likely) or it's not gounding.

A clip-on jumper wire should prove that.

 

Great info Pat, you may have just saved quite a few owners quite a few hours of frustration!

I'm going to check the owners manual for that very interesting location for fuses. Wonder if it's it in there...

 

I didn't see it there yesterday. It looks like it was from the factory job, but ya never know it could of been added by someone before me. let me know if you have fuses there too.

 

That little box is not there on my 06 tacoma. Maybe its located somewhere else...

 

Checked tonight while working on the truck and found no fuses in the rear frame rails or in the owners manual, but mine is a 2009...