Does the Brake Output Wire Get Attached to a 12 Volt Trailer Battery

Question:

I just bought a tandem axle trailer with brakes on the front axle only. I am rewiring the trailer because the wiring was ground off because of the previous owner. I have run my wiring for my lights and back up lights but I am not sure what I need to do to be able to wire my trailer brakes. I understand that one of the wires from the trailer brake goes to ground and one to positive, but do I need a 12v power source for the magnet to work or does that come from the truck when you hit the brakes? Do I need a battery for them to work? I will be using a 7 pin connector. This is my first time doing this so I need as much help as I can get! Thanks!

asked by: Bryce D

Expert Reply:

In order to rewire your trailer, I strongly recommend you use the Trailer Wiring 7-Way Upgrade Kit part # HS381-9000 with the Bonded 4 Wire part # 16-4B-1. This is going to ensure you have all the correct wire gauge and the junction box makes for a clean install as well as an easy way to troubleshoot if you ever have issues. In regards to the brake output wire part # 10-1-1, this will receive power from the tow vehicle's brake controller via the 7-way, not a battery during normal braking. However, by law you will also need to have a breakaway system, the Curt Soft Trac II Trailer Breakaway Kit part # C52026 which will energize the trailer brakes if the trailer becomes disconnected from the tow vehicle.

I have attached a generic breakaway install photo for you.

expert reply by: Conner L

click to enlarge

Cecil H.

8/12/2020

I have a 2015 Chevy Silverado 1500 when I hook my trailer up I start driving how do I get the message comes up trailer disconnected I've changed the plugin truck and trailer

Jon G.

8/26/2020

Does your trailer have LED lights? Sometimes the truck doesn't recognize that a trailer is connected because the LED lights don't draw enough power for the truck to "see" that it's there - especially if it's a smaller trailer. To remedy this you can add the Lamp-Out Sensor # 20142 which adds more of a load, but I'd double check all your wiring and maybe test your trailer with another vehicle and your vehicle with another trailer before sinking any more money into it.