1986 Mazda B2000 boat trailer lights

Need info on hooking up lights to truck. I am using 4 pin I hook it all up and taillights and blinker works, but when I tie in brakes the brake and blinker lights come on together. I remember I had a 87 Mazda pickup and I'm thinking I had to buy a light adapter to make this work. I've tried and just can't get it to work I'm pretty good on this stuff but it's got me puzzled any help you have I would appreciate it!

Correct: you need a converter. Trailer shares bulb for brake lights and turn signals, the Mazda truck (and many other vehicles) have separate bulbs for these. Contact etrailer.com https://www.etrailer.com/Custom-Fit-Vehicle-Wiring/Curt/C55304.html?feed=npn&gclid=EAIaIQobChMIlvvDtOuT2AIVF9RkCh2fuQWqEAQYASABEgLSW_D_BwE

For my '98 Frontier I was able to get a plug-in kit for such trailer hook up, included the converter.

Thanks for the info!!

Ok hooked up converter, taillights are only thing that will come on, no brakes or turn. Ground is working because taillights work great. I took light off trailer and hooked it straight to plug coming out of truck and still wont work! Losing my mind trying to figure this out!

Is there a chance you are using "scotchlock" connectors to tie into the truck wiring harness? I have had really iffy performance out of them anytime I have tried to use them. If you have a test light, you should be able to ground it and stick the pointy end into the wires to see if they are getting electricity from the truck harness.

I would never use those, even for a stereo connection; I've seen those in some kits. I always solder trailer or stereo wires.