How To Wire Trickle Charge For Battery On A Camper Trailer

Question:

Set up with the 7 pin but someone cut off the connector now when connecting it to the 7 pin on my truck how do I trickle charge the battery on the camper trailer? Does the camper trailer battery go to the negative on the 7 pin? Where does it ground as this is my first trailer setup and I want to do it right. Also do you recommend running a fuse so that there is nothing to short in back through the 7 pin? I am also looking for a waterproof fuse block to run on all my other lights in case they short out so it doesn't come back up through the 7 pin. Thank you

asked by: Jay

Expert Reply:

To begin, you would need to install a 7-Way connector on the trailer. Since you will need several things including connectors, I recommend going with the Trailer Wiring 7-Way Upgrade Kit, Item # HS381-9000, to make your project easier. It has a 7-Way connector, junction box, wire loom, and the hardware you need.

Your trailer wire colors may be different so you have to wire in the new connector function to function, not color to color. To determine the functions of the wires, touch each of the wires to the positive side of your battery and see what lights up then label each one by function. Connect your wires together and you will be good to go.

To maintain power to the battery, you need to run a wire from the positive terminal on the trailer battery to the power wire on the 7-Way connector in the Item # HS381-9000 kit, which is for 12-volt power. I recommend using 10 gauge wire, Item # 10-1-1, and connecting to the Black wire on the trailer 7-Way to the positive battery terminal (see FAQ article). You then connect the negative terminal to a clean metal surface on the trailer frame for a ground connection.

You will not have to worry about shorts because you will have protection built into your truck connector and the trailer connector. However, always good idea to have a 40-amp breaker for any 12-volt charging circuit.

I have attached additional information for you to check out that should help.