Inside trailer lights...???

dbart

dbart

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I have a 16' box trailer that has (2) LED lights in the ceiling run off a switch on the wall.

The thing is, they only work when my trailer is plugged into my truck.

I'll tell you straight out, I am not an electrical guru...in fact I hate electrical stuff.

Is there an easy way to do a bypass to where the lights work of either this batter off the tongue or to the car battery I have inside the trailer?

Hopefully without digging behind the walls and re-routing it all..???

Help me Obi Wan....you're my only hope!

:lmao:

:dbart:

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That little battery is for the brakes if the trailer comes loose.

 
you have to add a car battery to the trailer.  You can get away with a small Motorcycle battery 

 
I have a car battery inside.

Ok, So I probably just need to see what color the wires are behind the switch, see where they come out in the little battery box on the tongue, then do a bypass back to the battery I have inside or to the inverter I have???

Sounds complicated enough...I wonder how many beer job that is?

:lmao:

:bag:

 
To the battery not the inverter. Those are 12v lights and the inverter is 120v. 

Run the + and - to the battery and put in a inline fuse on the +. 15 or 20 amp fuse should be fine. 

 
Love this site...

Thanks for the info.

Now let's see if I can actually pull this off!

:laugh1:

 
RIDERED said:
To the battery not the inverter. Those are 12v lights and the inverter is 120v. 

Run the + and - to the battery and put in a inline fuse on the +. 15 or 20 amp fuse should be fine. 
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Connect the wire on pin 4 (red generally) on the 7 way to the battery you have in the trailer.  Fuse it as said above.

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This will let you charge that battery with the truck while in transit as well.  Not much, mind, but some.  Most  likely your truck has protection for this to prevent the trailer from discharging the truck, but best to disconnect when camped to make sure.

 
Rockwood said:
Connect the wire on pin 4 (red generally) on the 7 way to the battery you have in the trailer.  Fuse it as said above.



This will let you charge that battery with the truck while in transit as well.  Not much, mind, but some.  Most  likely your truck has protection for this to prevent the trailer from discharging the truck, but best to disconnect when camped to make sure.
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Probably not if the lights only work when plugged into the truck.

Dale, is your inverter wired into the MC battery?  As been said, you would tie your MC battery into the circuit the lights are on.  This would allow you to run the lights of the MC battery, and the truck.  It will also allow the truck to charge the MC battery when the trailer is plugged in.  You will need to remember to unplug the truck when you get to camp.  The inverter, and lights, could kill the truck batteries if left plugged in for an extended period.

A project like this, even for a seasoned wiring guy, would take all day.....if his beer fridge were properly stocked.  :sraptor:

 
What kind of "Atmosphere" are you going for in the trailer?

So many battery powered LED options...

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Keep your eyes and ears open for a used solar charger. Something small and portable to maintain the battery and to give it a few amps while out camping in the sun. 

Also keep your ears open for a used battery for cheap or free. You want a deep cycle 12v battery. Or a marine/rv battery. What you do not want is a 12v car battery for starting. Its all good if thats what you have now. But in the future a used deep cycle would be nice. I see used batteries show up on this site from time to time. Youre such a nice member i could see someone just giving you one. 

 
You might look under the trailer where the switch is located to see if they ran the wires there. 

 
you could put a isolator on the battery in your trailer to keep the truck from discharging when is it turned off   https://www.amazon.com/WirthCo-20092-Battery-Doctor-Isolator/dp/B0058SGDFK?th=1    like said above tap the red wire and run it to the aux battery with a fuse at the aux battery........               these isolators work good i added a extra battery to my toy hauler just for the generator because with the heat on all night sometimes the gen would not start. the rv generators do not have a charging circuit built in so you need to charge from the charger built in for the house battery's. so i needed this isolator to keep the generator battery charged. it disconnect when the charger shuts off 

 
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Ok, I started thinking about this a little more and I think I was over complicating things.

Looking at where the wires are, everything is hidden. there is also a cig adapter and 2 usb plugs I would have to chase as well. UGH!

My trailer plugged into my truck works my lights Cig Addapter/USB inside and that uses the 7-way connector right?

Well, my thought is to get the 7-way connector (male end) and mount that to the front of my trailer (see pic).

I then wire that aux wire from the 7 pin to my batter with a fuse and ground the battery to the frame.

So, when I pull into camp I unplug my trailer from my truck and then plug it into the front of my trailer and Ta DA! I have lights!

Well...in theory.

I ran this by my buddy who's an electrician and he thought that actually sounds pretty good!

Also, seems to be maybe 2-3 beer job...again, that's in theory! :laugh1:

:dbart:

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