Go Back   iRV2 Forums > MOTORHOME FORUMS > MH-General Discussions & Problems
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 01-23-2013, 09:24 AM   #1
Senior Member
michguy's Avatar
National RV Owners Club
Join Date: Mar 2010
Location: Spring Lake, Michigan
Posts: 298
Question Coach Batteries: To disconnect or not?

We're in Florida for 2 more months, hooked up to 50 amp power, and it just dawned on me that I have no idea why I haven't hit my " Battery Disconnect " switch. Now, I'm wondering whether I should, or whether I shouldn't. What is your opinion?

Coach: '05 National TropiCal T370 Toad: '07 Saturn Aura Blog:On The Road With Dar 'n' Don
michguy is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 01-23-2013, 09:30 AM   #2
Senior Member
Sky_Boss's Avatar

Newmar Owners Club
Spartan Chassis
Join Date: Apr 2012
Posts: 5,570
I would leave it on. That will allow your converter/charger to keep your house batteries charged. If you have something like a BIRD or Trick-L-Start then you also keep you chassis batteries charged too.

Don, Sandee & GSD Zeus. Gardian Wings earned are GSDs Gunny (7/11/15) & Thor (5/5/15)
2006 DSDP 4320, Spartan MM IFS, 2013 CR-V, Blue Ox Avail, SMI AF1, Samsung 197R Refer.
Sky_Boss is offline   Reply With Quote
Old 01-23-2013, 09:35 AM   #3
Senior Member
PDR John's Avatar

Join Date: May 2012
Location: Lighthouse RV Resort, Melissa TX
Posts: 3,561
I've never flipped the switch on either of my coaches. If it's plugged in I let the charger take care of them.
2013 DSDP 4347, all electric, 450 H.P. ISL
Air & hydraulic leveling
14 Jeep Grand Cherokee Overland toad
PDR John is offline   Reply With Quote
Old 01-23-2013, 10:02 AM   #4
Senior Member
Qwert66's Avatar
Newmar Owners Club
Join Date: Nov 2011
Location: Michigan
Posts: 680
Send a message via Skype™ to Qwert66
Why - There are items on your rig that only run from 12vdc. These items are usually fed from the chassis/coach batteries even when plugged in. When disconnected you may not be charging the batteries thus running them down. The disconnect switchs are for when you are storing the rig (and/or trouble shooting) with no external power connected to stop the drain from residual sources like dash radio, cb, lp detector if not turned off, furnace/hw heater/ fridge control boards, antenna booster if not turned off, engine and tranny ecm's, security systems, gps's etc.
If plugged in leave the coach and chassis disconnects on as stated earlier.

This assumes you have a decent multi stage battery charger (converter) that will not boil out the batteries when left on and that you need to use some of the items mentioned above.
1999 Newmar Mountain Aire MADP 4080, Cummins ISC 8.3L, Allison, Spartan MM IFS, Howard Power Center, Chev Trailblazer LTZ Towed w/ BlueOx rigging, Segway X2.
Qwert66 is offline   Reply With Quote
Old 01-23-2013, 10:15 AM   #5
Senior Member
Sky_Boss's Avatar

Newmar Owners Club
Spartan Chassis
Join Date: Apr 2012
Posts: 5,570
Even with the batteries disconnected by the switch there are phantom draws and battery internal resistance that will drain batteries. My Winnebago was real bad in this area. I never did figure out why it drained so easily.
Don, Sandee & GSD Zeus. Gardian Wings earned are GSDs Gunny (7/11/15) & Thor (5/5/15)
2006 DSDP 4320, Spartan MM IFS, 2013 CR-V, Blue Ox Avail, SMI AF1, Samsung 197R Refer.
Sky_Boss is offline   Reply With Quote
Old 01-23-2013, 11:06 AM   #6
Senior Member
bruceisla's Avatar
Join Date: Oct 2012
Location: Land O Lakes, FL
Posts: 3,992
If you search the forum for battery disconnect problems you will find multiple entries. Basically, the battery disconnect that is implemented via switches near the entry door is an overly complex pile of unreliable parts waiting to cause grief. Not touching it seems the best bet. The much older technology "hardware rotary switch" similar to what is found in boats is usually simple and reliable. Once again, the KISS system is best.
bruceisla is offline   Reply With Quote
Old 01-23-2013, 11:55 AM   #7
Senior Member
Join Date: Nov 2005
Posts: 3,049
If your coach is wired anything like ours you can't shut off the batteries and expect any of the lighting or other 12 volt systems to operate. The lights and refrigerator control board draw their power from the batteries. If the batteries are disconnected they will not work. Also the inverter/charger won't charge the batteries if they are disconnected.

The only time we disconnect the batteries (engine and coach) is when the motorhome is in storage. Then there are no parasitic or phantom loads to run them down.
2013 Adventurer 32H
Hikerdogs is offline   Reply With Quote
Old 01-23-2013, 12:05 PM   #8
Senior Member
YC1's Avatar

Holiday Rambler Owners Club
Join Date: Jun 2011
Posts: 4,573
Even if disconnecting the batteries via a physical turn switch what will happen if shore power goes off? Your refer will not function and spoiled food.

Turning off the switch by the door will only turn off some things inside that you really want working.

Depending on your wiring, shutting off the batteries via battery switches in the battery compartment they should be completely isolated which means no charging and no draining other than self discharging over a period of time.
Myron & Deborah
08 HR Endeavor 40 SKQ
2012 Ford Edge Limited FWD 3.5L
Aluminator tow bar, Demco base plate
YC1 is offline   Reply With Quote
Old 01-23-2013, 01:26 PM   #9
Senior Member
Join Date: Jan 2012
Location: seattle, wa.
Posts: 413
Send a message via Skype™ to LandKinaMoho
I reckon if you dont want any lights, furnace etc to work go ahead.......lol.
1999 National Dolphin
1995 Range Rover County SWB.
Sailor, Dickens, Zooki, Koko.
LandKinaMoho is offline   Reply With Quote
Old 01-24-2013, 06:45 AM   #10
Senior Member
Cat320's Avatar
Fleetwood Owners Club
American Coach Owners Club
Join Date: Mar 2011
Posts: 4,170
I'm always on shore power, and never turn the 12v switch off.

2014 American Eagle 45T
DD 500
Pulling a Honda CRV
Cat320 is offline   Reply With Quote


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

» Virginia Campgrounds

Reviews provided by

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 11:35 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.