Trailer lights work on some trailers but not another

I just bought a new boat with surge breaks. My truck when hooked up won’t get any power to the trailer lights. I hooked the truck up to another trailer and all the lights work. I then hooked up a different truck to the boat trailer and all the lights work. Can’t figure out why it wouldn’t work with the tundra. Any thoughts?

 

Two types of light set up you might need a converter

 

Sorry if this sounds dumb. But what do you mean two type of light set ups?

 

So there are trailers that use brake and turn signal on one bulb and other type there are one bulb for brake and another for turn signal

 

Yellow is for left and green is for right signals red is for brake blue is for trailer brake brown is for parking and white is for ground

 

Oh I gotcha. Shouldn’t it still work since all the signals in the seven prong plug work on the other trailer? Both trailers are 7 prong one just has electric brakes and the new trailer has surge brakes. I even tested the plug with a tester and everything works it just won’t get any power to the new trailer.

 

Grounds good

 

The ground on the truck is working. And the one trailer plug worked fine on another 2 trucks.

 

Are you using a power probe

 

Yea that’s what’s weird. Everything has power when I test it with the probe. Just won’t work on this new trailer. Idk if it’s because the truck isn’t registering a trailer or what it’s just odd.

 

Are the lights all led lights on trailer

 

Yea they are. All of them.

 

Not sure if there is a trailer module Maybe it needs more load to work

 

I’m not sure. I hadn’t thought of that I will look into it. Thank you for your input!

 

Do u have standard oval lights on trailer

 

Swap filament bulb trailer light see what happens

 

I’ll give it a go and report back.

 

I’ve got electric trailer brakes but with the exact same issue. All my (1500lb) utility trailer lights work and the truck recognizes it being plugged in but the brakes wont engage even at level 10.

Towing my 7k lb camp trailer and the brakes/lights work just fine. Tow another heavy utility trailer and the brakes/lights work fine.

Dealership tested entire trailer brake system. All AOK.

Conclusion (best guess): the truck somehow recognizes the lighter trailer weight and responds accordingly.

 

I have had the issue with small trailer brakes. Had a trailer company tighten the calipers and solved that issue. Found the issue with the boat trailer. Seems there is either a small short in my truck connection or new trailer plug is a little smaller than all my other trailers. Never had the short be a possibility. But when wiggling connection (because there is wiggle room, found the sweet spot). Will have to duck tape connection until I swap either truck or trailer plug.

 

Very cool.