Electrical Issue with my Trailer

[LovinPowell]

I am hoping that somebody could help me with an electrical issue on my trailer. When my lights are on, the blinkers don't work properly. With the right blinker on, both taillights blink (as if they were on hazard). With the left blinker on, neither blinker works on the trailer. When the brakes are pressed, both taillights go dim. During the day, it appears as if all of the lights are working properly.

Is there someway that I could test to see where a short might exist? Is there some kind of electrical tool that would help to determine/fix the problem?

Obviously I am not very good when it comes to electrical trailer problems, so any help would be appreciated.

[lee]

With a test light or volt meter you could test the wiring on the tow truck to see if that is the problem. Your groung wire on the trailer might not have a good conection either.

[Tequilasun]

As lee stated above.

I've found that most weird problems with trailer lights lead to the ground wire. Either it is not grounded well enough to the trailer (so trailers don't ground to themselves at all, though) or the tow vehicle ground is not solidly connected.

[Boarder_X]

I had that same problem. My left blinker/ brakelight/ running light (the red light) had water in it. I replaced it, and everything works great now. With the water inside, it still works, but it shorts out the signals, and so it does wierd things.