How To Keep Trailer Battery That Powers Winch Charged While Its Being Towed

Updated 08/17/2021 | Published 08/16/2021

Products Featured in This Question

Bulldog Winch Rear Wiring Kit - Quick Connect to Terminal End - 3 Gauge - 24' Long

(9)

$236.40

10 Gauge Wire - Blue Primary - Per Foot

(102)

$1.77

Ring Terminal - 12-10 Gauge Wire - 3/8" Ring ID

(65)

$1.82

Deka Battery Isolator - 120 Amp

(44)

$101.65

Question:

Iv just read this bellow, and I need to do exactly the same. My question is, how do I connect it to the battery in the trailer? Question: I need to charge a marine 12v battery that powers a winch and tongue jack in a 24inch enclosed race car trailer. The tow vehicle is a Toyota Tundra and has 7 pin round connector. I want the trailer battery to charge from the Tundra when the 7 pin is connected. asked by: Joseph F Expert Reply: You can put a maintenance charge on your trailer battery with the 12 volt accessory circuit of the 7-way. The 1:00 position of your 7-way carries this circuit. You would just need to run a length of 10 gauge wire like part # 10-1-1 sold by the foot, from this pin to the positive terminal of the battery. You should note that this wont charge a dead battery, but it will keep the battery topped off when you are towing the trailer. expert reply by: Jameson C

asked by: Paul 8

Expert Reply:

I would be happy to help!

If the maintenance charge is enough for your battery, then running the # 10-1-1 from the 12v accessory circuit of your 7-way connector to the positive terminal of your trailer's battery using a ring terminal # DW05705-1.

Keep in mind that this will not keep the battery from draining while using a winch or tongue jack, as this circuit does not offer much power.

To keep the battery from going dead a better option would be running the Bulldog Winch Rear Wiring Kit # BDW20026 from the battery of your tow vehicle to the rear of the truck, and then run the extra wire from the battery on your trailer to the tongue of the trailer. Adding the two included connectors to each set of wires will give you a way to connect and disconnect them when towing the trailer. I also recommend adding a battery isolator like the # DW08771 to keep your vehicles battery from being drained while it is not running.

This will charge your trailer battery from your alternator.

I included a video o the # BDW20026 for you to take a look at.