Trailer light troubleshooting help

[wishingiwasfishing]

Replacing the trailer lights on my kayak trailer. It’s just a 5x8 utility trailer from TSC.

I’m replacing the incandescent lights with LED lights and have tried 3 different models of light but they all do the same things which is....

When I turn on the turn signal or press the brake, the light works but is dim. When I just have the parking lights/headlights on, the light works and is in the bright mode. This is somehow reversed from what it should be. The dim mode should be for parking lights and it should go brighter when turn signal or brake is used which it does not.

What am I doing wrong? There are only three wires with one of them being a ground wire (which I have grounded). I tried reversing the wires but then nothing works. The plug to the vehicle is the flat 4-wire connector type.

Thanks in advance.

[Terrierman]

If you have a tester - find the running light on the vehicle.  Connect brown wire to that one.  Then keep checking.  Green wire to right turn, yellow wire to left turn.  White wire is ground.

 

[wishingiwasfishing]

I appreciate it Terrierman but that is how they are connected. If the wires are switched, no lights work at all.

[aarchdale@coresleep.com]

First thing i would do is hook the trailer up to another truck.  Make sure it is the trailer and not the truck

[wishingiwasfishing]

The incandescent lights that I am replacing work as expected when connected to the same vehicle. Been pulling this trailer with this vehicle for years.

[fishinwrench]

Post a pic of it hooked up to the truck.   Include in the pic the connectors and the trailer ground connection (white wire).    

Before you do that, take a volt/ohm meter and verify continuity of the TRUCK SIDE ground terminal (that's the odd shaped terminal in the plug).   Make sure that terminal has continuity to the frame of the truck.