Current to Trailer When Ignition Off?

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jwhite

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Hello,

New Ram owner -- 2004 with 5.7 Hemi, factory tow package. It has an electronic brake controller and a 7-pin harness connector.

We will be towing a travel trailer and doing a lot of boondocking. Is it necessary to unplug the trailer wiring harness/umbilical/pigtail from the truck to avoid draining the truck's battery while using 12 volt lights and appliances in the trailer? (The trailer has it's own battery.)

I've heard that in most vehicles, current will continue to flow through the wiring harness, from the truck to the trailer, even with the key off. But some vehicles have an automatic, built-in feature that prevents this from happening.

Thanks in advance for your help.

Jay
 

Marley

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Been towing travel trailers for over 20 years and always unplug.

You'll find that getting the trailer level will require unhooking in most cases and it's not good on the trucks suspension to support the tounge weight for extended periods.

I say unhook, unplug.
 

rule18

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Been towing travel trailers for over 20 years and always unplug.

You'll find that getting the trailer level will require unhooking in most cases and it's not good on the trucks suspension to support the tounge weight for extended periods.

I say unhook, unplug.

^^This for sure.
 

crash68

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Whether you need to unplug depends if the +12V of the trailer plug is just to recharge a dedicated break away battery or that battery feeds the whole trailer.
It's probably a good idea to get in the habit of just unplugging the trailer when you stop for the night and replug it in during the morning walk around check.
 

Smokeybear01

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I have always unplugged just as a matter of course and then in the morning when the trailer battery is dying from running the furnace all night or having the lights on all night while playing cards and drinking... that's another story. Anyway, then plug it in and fire up the truck to recharge the trailer bats. Some trailers, very few, actually have a dedicated (small) battery just for the trailer brakes in case of a break away incident. But that is uncommon on travel trailers, mostly utility or boat trailers. Good luck and enjoy,
 
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