Battery connections when hooked up

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Rob&Deryl

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Tonight we are actually boondocking (ok, overnight parking) for the first time.
I am running the furnace and while I know I have sufficient battery, since we are still hooked to the truck, will we drain the truck battery too?
 

NY_Dutch

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Where our wheels take us!
As I recall, RAM uses a straight from the battery fused feed to the 7-pin connector. It wouldn't be too difficult to add a relay to turn it off when the key is off. That's the way Ford does it...
 

Rene T

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Farmington NH
I understand there are provisions in the truck to stop from draining the battery from the truck. Even knowing that, I use to always just walk behind the truck and unplug the cable just in case.
 

Mark_K5LXP

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It's a percentage thing. If your house batteries are 200Ah and you use 50Ah, they're down 25%. If you add in the truck chassis battery you increase the total Ah capacity by some amount, say 100Ah, so for 50Ah the now 300Ah 'bank' sees just a 17% discharge. Overall chassis batteries are not a good thing to deep cycle frequently but depending on circumstances and convenience factor, there may be a decided advantage or disadvantage to have this extra capacity on tap so I wouldn't consider the disconnect a must/never thing to do but would consider if it would help or hurt for any given stop.

Mark B.
Albuquerque, NM
 
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Gary RV_Wizard

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At my Silver Springs FL home
The smart thing is to disconnect from the truck. Always. If you run the trailer battery down, you can always reconnect (and start the truck engine to keep the charge up), but that's better than discovering the truck battery is dead when you get ready to leave.

The furnace fan can suck a lot of battery amp-hours on a chilly night, and that's in addition to lighting and other uses. Don't risk a surprise.
 

Kirk

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Oct 30, 2005
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Full-time , Escapee
will we drain the truck battery too?
Normally the answer would be no, but to be sure would require more knowledge. IF your trailer is plugged into a connection that was factory installed on the truck or was properly connected by an after market installer, turning off the ignition key also turns off all power to that plug. But I do like most others here and pull the trailer plug when I stop for the night because relays and such do occasionally fail and it takes little effort to do that and then reconnect in the morning.

One thing that I do when stopping for the night is to hang the ambilocal cord for the trailer over the tongue jack which is used to stabilize the occupied trailer, thus making sure that I will not forget to reconnect it before driving away.
 

Rob&Deryl

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Mar 27, 2017
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On the road from mid NH
I disconnected it. The truck has 2 group 27 batteries.
I though about dropping the landing gear to stabilize but didn’t. The wobble was only noticeable when sitting and some one else was walking. No issue sleeping.

We do a light check before moving and drive with lights on so if I forget to plug it in, we should catch it. 2nd chance to catch it is when I do a trailer brake test & 3rd would be no trailer connected message on the dash.
 

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