How to charge a trailer battery with a 7 pin plug

Dan charges the trailer battery with the Topdon Tornado 4000 and adds wiring to the trailer to make sure he never has to charge it again.

©2022 Dan's Garage NC

Episode: 0102
Vehicle: Car Trailer
Work: Charging the battery and adding wires to the trailer so he never has to again.

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[bobdavis]

Amazon or any large RV store will have a heavy duty on/off switch so you don’t need to disconnect the battery cable to the winch every time you use it.

[heribertoperezteran]

Can trailer battery start a truck in case of low or death battery ?

[larryseibold]

What does the 4A charger in the first half of this video have to do with the 7 pin plug charging of the winch battery?
What is the fuse rating that feeds that 7 pin connector? How does operating a winch (~300A) not blow that fuse while it is connected, even it the second battery?
Did you install a breaker as you mentioned or rather a fuse (replaceable vs resettable)? What amperage did you install in the positive line?

[anthonyspadafora]

The 12 volt terminal on the truck side of the plug, isnt that a much smaller wire? Does that wire also have a fuse?

[JamesJones-thmi]

Do you have to mount a negative wire as well or is it because it's already grounded and all you need is

[ntme]

I've always wondered what regulates the amperage on the 7 pin 12 volt. What voltage does it charge at when the truck is running? Is it 14.4 just like the battery under the hood?

[bryanmccammon]

What size circuit breaker did you install. I'd like to do what you did but with a 1000 watt power inverter instead of a battery

[heribertoperezteran]

Are there any risk to damage electrónics in towing vehicle( overvoltage or something)?

[chickenfoundation]

What about the ground? Does the battery ground to the trailer frame or does it need to ground to the harness?

[shekharmoona]

Can you charge a travel trailer battery while it's in it's cradle with a regular harbor freight car battery charger? (Microprocessor charger)

[rustyedges]

For the power converter you bought how do you like it now after you're using it for a while?

[danielfam]

Do you need to have a DC to DC battery charger for that?

[JamesJones-thmi]

Cuz what I was thinking of doing is tap into that pigtail running the wire to the positive and then for the negative just running in a separate wire from the battery to the fame

[Johnstonfamily]

Any issues with the battery back feeding lights or anything? Someone told me I needed to add a diode inline

[joebieber]

Did you run a ground wire from the plug to the negative post on the battery?

[gadsdenconsulting]

Thanks for posting this. I may have missed it, but how are you powering a 110v charger, using a 12v power supply from your 7-way plug?

[lolobernal]

This lil girl must be a star now. Def in tv somewhere maybe BGC

[michaelrudd]

I don't have shared comment what is cuz I don't know where it come from

[brandonhamner]

Just curious on what would happen, if anything, if you spliced from the hot wire on your 7 pin trailer harness as well as a ground wire (adding battery clips and a way to quick disconnect from harness slice) to the trailer battery. Would there be enough power to operate the winch at all? Would it charge the battery any if you left it hooked up while the vehicle was running?

[simpleman]

Hey Dan, I am looking into buying a Max Built ca hauler and I saw your video about a year ago. How is the trailer holding up? Would you recommend it?