I have power before the black box because all of the lights work except for the left turn signal
and by the way what is the black box called??? sorry I am a new LR owner....

 

Ok, why doesnt the left turn signal work? Is the bulb burnt out? That might be why your trailer lights dont work, so fix the left turn on the trk first, the black box should work then.
And I do not know what that black box is called, lighting adaptor maybe?

 

Spike 555 the truck turn signals work fine and the "flasher units" as well
the only thing that doesnt work is the trailer left turn and I did check the trailer bulb
and switched with the other side and works fine I even made a test light and at the 7 pin
plug all work except for the left turn I'm gonna bet then its the box Ill have to check into finding one
Thanks

 

Ok, I miss understood you, I thought that you said that the turn on the trk wasnt working either.
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