How To Wire and Install On-Board Auxiliary Trailer Battery to Power Lights

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Question:

I have an enclosed snowmobile trailer, I want to add an auxiliary battery to power interior led lights, also add a battery tender, Im looking a wiring diagram to do this with an isolater, so I dont drain the breakaway battery, or back feed from or to the vehicle? Can you help me

asked by: David H

0

Expert Reply:

In order to charge an on-board trailer battery you'd need to have a seven way connection on both the vehicle and trailer, this would contain the necessary circuits to pass a charge from the vehicle battery to the trailer battery. If you don't already have one on the trailer you can use the Junction Box # 3375601101 and 7-Way Connector # H20046. If you don't already have one on the vehicle we'd need the year, make, and model to inform of options. The seven way would then contain a circuit called the "battery charge line" or twelve volt power" which would be used to provide a small trickle charge to an on-board trailer auxiliary or breakaway battery.

In all honesty, if you were simply using the on-board battery for some lights inside the trailer you probably wouldn't even need to worry about draining the vehicle's battery assuming there wasn't any sort of backfeed protection built into the vehicle's trailer wiring circuits. That said, I understand wanting to be safe and not sorry so in which case I recommend the Redarc In-Vehicle BCDC Battery Charger part # RED96FR which does a few different things. It will not only make sure there is no backfeed but it will also ensure your trailer battery is fully topped off at all times. It will only pull power from the vehicle battery when it's receiving a charge from the alternator. The "battery charge line" or twelve volt power" circuits from the vehicle only provide a trickle charge whereas this unit will provide a full charge. I like this option for you as it opens the door for you to power other accessories from the battery without having to worry about a dead battery.

I have attached a wiring diagram below.

expert reply by: Conner L

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How To Wire and Install On-Board Auxiliary Trailer Battery to Power Lights
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Answer 1

Hi Walter, For the Deka Battery Isolator #DW08770 you can go with 8 gauge wire. Deka actually makes an installation kit with this wire, the Deka Battery Isolator Installation Kit for Standard Alternators #DW08769.

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Answer 2

Since you've already got a 4 pole on your trailer, you'd just need to add a 7-way with #ETBC7 so that you can run a charge line using #10-1-1 from the accessory circuit to your battery. This circuit is located at the 1'oclock…

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Answer 3

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Answer 4

Hey Bryan, yes the ZCI kit part #119250KIT does 2023 Tesla Model 3.

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Answer 5

If I'm understanding you correctly the starter solenoid #PK5231201 is not the solution to your problem. Based on what you have described, it sounds like both the breakaway battery and winch battery are hooked to the 12V power coming from…

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Answer 6

You will want to run the 12V wire from the 7-way trailer connector to the positive terminal on the larger battery. Then you will want to connect the larger battery to the breakaway battery from positive terminal to positive terminal, using 10 gauge…

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Answer 7

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Answer 8

The difference between the Firestone Dual Air Command Systems #F49VV and F46VV is the the former is only controlled by a smartphone while the latter can be controlled by a smartphone but it also comes with a Bluetooth remote so you don't have to…

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Answer 9

I recommend a 12 volt car battery rather than a breakaway battery because you may end up needing the larger battery down the road. What you will do is attach a battery box (see link for options) to the trailer frame. From the trailer side 7-Way…

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Answer 10

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),…

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Answer 11

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Answer 12

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How To Wire and Install On-Board Auxiliary Trailer Battery to Power Lights

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