How do you wire a 4pin for brakes
 

So I searched and couldnt find anybody saying exactly what i need to do to get my trailer brake lights to work. I am trying to hook up a four pin connector to my trailer for brake lights, i have running and turn signals working fine but I dont know how to make brake lights work since toyota's brakes are different than the turn signals. truck is a 90 pickup. Thanks.

You need a 5 wire to 4 wire converter unit.
Easily got at any auto parts place.
Instructions will come with it.
Shop around, prices vary a lot.

Here you go...you need this. I'm sure they also sell them at NAPA, Wally World, Advance Auto, etc....

Before you buy anything, look underneath the rear of the truck and make sure there isn't already a trailer wiring harness tucked up there somewhere out of sight, ready to hook up. Mine had everthing I needed ready to go, just needed to connect the various wires. Mine came with an OEM trailer hitch, so maybe that's why.

If the wiring harness is there, it will likely be thoroughly covered with tape and secured in place, so you might need to look pretty carefully.

thank you, I bought the converter and wired it up. I am a little confused on how running lights are separated from brake lights, my trailer's lights are a single large bulb in the middle with a separate little bulb and housing attached to that one, it looks like they are wired together. So my question is do I need a brake light with 2 bulbs in the main light. Cause right now it looks like 12v runs to the both the large and little light when runners are on and then 12v is sent again for the brake light. I dont see how 12V again would make it much brighter.

Usually the "large bulb" in the middle is a dual-filament bulb, with two bumps on the bottom. One filament is for brakes and turn signals, and the other for running/tail lights. There should be two connections to the main light, one for each filament. And no, the brake light 12V does not connect to the running/tail light 12 volt.

Ahh ok, that makes sense now. Thank you very much!