Can someone tell me what a brake controller does?
 

Hi I bought a 2002 2500 used, and it has a brake controller, to make brakes harder or softer for towing, I dont tow anything so i was just wondering what it does and what systems it affects. Thanks i'll try to post the make and model to give you guys a better idea. Happy Holidays.

it will add or reduce voltage to the electric trailer brakes. If its the inertia style, the harder it senses the truck slowing the more voltage applied. Regular you need to set the amount of voltage so one voltage is sent everytime you step on the brakes no matter how hard or soft the stop is.

it won't effect anything just being on there. It should just plug into the wiring harness under the dash. When you apply the brakes it sends an electric current to the trailer plug out back. If your ever towing a trailer that current will apply the brakes on the trailer.

Thank you everybody,
Happy holidays