The only way your headlights can come on when you press on the brake pedal is a crossed wire. The brake light wire and the headlight wire can be frayed and touching each other.
i found it to be the tail light harnesses go bad . a common problem with them because the bulb sockets short out.
you probally need to replace the bulbs
just as the name it makes the brake lights come on when u press on the brake pedal
Under the brake pedal is a brake light switch that when you press the pedal it hits it and makes your lights come on..sometimes when they get weak the pedal depresses them simply from the weight of the pedal and they stay on..Have a friend get inside the truck and pull UP on the brake pedal as you look at the lights..if the brake lights go off when they pull up on it..then it is that switch under the brake pedal
More than likely there is a switch near the top of the brake pedal that is faulty. It usually looks like a small button that is released when you press on the brake pedal which turns on the brake lights.
it's somthing under the brake pedal, it's sticking and just needs to be loosened. you'll also find when you press the pedal in, the brake lights will go off.
put your foot on the brake pedal and press down while some one looks at the brake light to see if it lights up
if you have no brake lights it will most likely be one of 3 things a blown fuse bad ground wire or under the brake pedal you will find a small switch that the pedal hits when you press on the pedal the switch does go bad but is easily replaced and usually not too expensive
Check the fuse, bulbs and actual regulator switch in that order
You have a poor or no ground between the vehicle and trailer.
Adjust or replace the stoplight switch at the upper end of the brake pedal under dash area