How to Wire a Break Away Kit Used for a Proportional Brake Controller on a 2008 Chevy Silverado

Question:

I have two questions First I have a dump trailer that has on battery on the trailer. I want to wire it up to charge the battery. It looks like they ran a wire from the positive side of the battery to the Aux power coming from the truck. I measured the voltage in the wire coming from the trailer battery and it is 12 volts. If I hook up the 12 volt wire coming from the truck Aux 12 volt to this wire will it not short out two different potentials??? I have a break away switch that has a black white and blue wire coming out of it. Black wire goes to power from trailer battery + ? White wire goes to the trailer frame? The blue wire gets spliced into the wire running to the trailer brakeshopefully blue ? Thank you for your time

asked by: Andy

Expert Reply:

A 12V circuit from the 7-way trailer connector will not charge a battery. The vehicles alternator does not have enough punch and the wiring feeding the 12-volt accessory circuit is not large enough in gauge to allow sufficient current to reach the battery and charge it. The circuit can be used to maintain a battery, but will not charge a dead battery. To charge a depleted battery you will need shore power and a charger like the NOCO Genius Mini # 329-GENIUS5.

Break away switches typically only have two wires, one of which splices to the electric brake wire coming from the trailer side connector and the other one connects to the blue wire on the break-away box.

Break-away kits that come with a built in battery charger have three wires which are typically black, blue and white. For this installation, your blue wire is already connected to the blue wire on the break-away switch, so you are left with a black and white wire. The white wire either splices into an existing ground wire on your trailer or grounds directly to the trailer. The black wire gets spliced into the trailer 12-volt auxiliary power lead.

I have attached the Hopkins BreakAway Kit # 20099 installation instructions as well as an installation video which may help.

expert reply by: Lori W