RV Trip Planning Discussions

Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login

Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  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 01-12-2019, 03:31 PM   #1
Junior Member
 
TMt2's Avatar
 
Join Date: Jun 2018
Location: Tampa, FL
Posts: 9
Help With House Battery Hookup?

New to me 2006 Coachman Cross Country 354 MBS (Freight-liner chassis DP) came WITHOUT house batteries in the bay. I bought 2 x 12V deep cycle AGMs (new) to install in the house battery bay. Coach/chassis Cables and lugs are present - seemed simple...but I’m having trouble and need help if anyone can?

Facts: 2 x 12V house batteries are in parallel (neg to neg, pos to pos). When I connect the coach feed cables (house bank) neg to neg battery 2 and pos to pos battery 1, I get BIG spark on Pos (coach cable) touching pos post on battery 1. Something isn’t right?

Some background:
1. 2 x Engine batteries are 12V in parallel (neg to neg and pos to pos) in opposite bay.
2. Coach and all equipment works fine in all states of power (shore, generator and on engine power) without house batteries (which is weird to me).
3. During connection and troubleshooting, the salesman switch is OFF and the engine/ignition are OFF.

My assumption is that the house battery circuit should be 12V?

I thought the house battery coach cables might have been mid-labeled so I tried a brief touch in reverse...Same BIG spark? It almost behaves as if I were grounding the system!

I put a volt meter on the disconnected coach (house bank) cables and had no reading between pos and neg?

I have not yet traced the house bank cables (in the chassis) to see where they originate from or if there is a common junction to the engine bank to permit house battery “boost” (I do have a momentary combiner switch in the dash, but haven’t used it).

I’d love to get house bank batteries working in the coach but am stumped as to what to try next?

Questions:
1. Where should I look for a short to ground?
2. Is it possible that it is 24V? All I’ve read says RVs are 12V systems?
3. Does anyone see (in my description of troubleshooting) that I’m doing something stupid?
4. Is it time to take it to an expensive expert?

Any advice is appreciated?
__________________

__________________
TMT2
2006 Coachman Cross Country - Freightliner) 384 MBS (Cummins 300 DP/Oman 5.5 Diesel)
Toad: 2016 Mazda 3 on dolly
TMt2 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 01-12-2019, 03:48 PM   #2
Senior Member
 
LJowdy's Avatar


 
Join Date: May 2013
Location: Ontario, California
Posts: 1,849
If you have an inverter, you'll get that spark when you hook up the batteries. You would have been better off getting 6 volt batteries. They provide more amps than 12 volt batteries.
__________________

__________________
2016 Newmar Dutch Star 4369
Newmar Owners Club
USAF 1966-1969,- Law Enforcement 1969 - 2003, Unemployed (retired) since March 2003
LJowdy is offline   Reply With Quote
Old 01-12-2019, 03:51 PM   #3
Junior Member
 
TMt2's Avatar
 
Join Date: Jun 2018
Location: Tampa, FL
Posts: 9
I have an inverter...but the salesmen switch is off? Wouldn’t the inverter also be off when coach power solenoid is not active?
__________________
TMT2
2006 Coachman Cross Country - Freightliner) 384 MBS (Cummins 300 DP/Oman 5.5 Diesel)
Toad: 2016 Mazda 3 on dolly
TMt2 is offline   Reply With Quote
Old 01-12-2019, 04:03 PM   #4
Senior Member
 
LJowdy's Avatar


 
Join Date: May 2013
Location: Ontario, California
Posts: 1,849
Don't know. I just know that when I've changed batteries and everything is turned off I get a spark when I hook up the batteries.

A good question for the inverter company
__________________
2016 Newmar Dutch Star 4369
Newmar Owners Club
USAF 1966-1969,- Law Enforcement 1969 - 2003, Unemployed (retired) since March 2003
LJowdy is offline   Reply With Quote
Old 01-12-2019, 04:11 PM   #5
Junior Member
 
TMt2's Avatar
 
Join Date: Jun 2018
Location: Tampa, FL
Posts: 9
The spark I got actually nicked the terminal post such that it was a bit harder to thread the nut...so I didn’t hook up thinking something is wrong.
__________________
TMT2
2006 Coachman Cross Country - Freightliner) 384 MBS (Cummins 300 DP/Oman 5.5 Diesel)
Toad: 2016 Mazda 3 on dolly
TMt2 is offline   Reply With Quote
Old 01-12-2019, 04:17 PM   #6
Senior Member
 
Join Date: Jul 2014
Posts: 16,515
Quote:
Originally Posted by TMt2 View Post
I have an inverter...but the salesmen switch is off? Wouldn’t the inverter also be off when coach power solenoid is not active?
No, inverters are not wired thru the house disconnect switch.

They can draw over 200 amps and the house disconnect can't handle that kind of amps.
twinboat is online now   Reply With Quote
Old 01-12-2019, 05:02 PM   #7
Junior Member
 
TMt2's Avatar
 
Join Date: Jun 2018
Location: Tampa, FL
Posts: 9
From both of your inputs...I can accept the big spark on hookup is normal. I will put in a fusible link before connecting just for the “if something is really wrong” factor. Any explanation why all electrical systems in the coach work (specifically 12V) when no house bank battery is is physically connected?
__________________
TMT2
2006 Coachman Cross Country - Freightliner) 384 MBS (Cummins 300 DP/Oman 5.5 Diesel)
Toad: 2016 Mazda 3 on dolly
TMt2 is offline   Reply With Quote
Old 01-12-2019, 05:26 PM   #8
Senior Member
 
LJowdy's Avatar


 
Join Date: May 2013
Location: Ontario, California
Posts: 1,849
If all the electrical items in the coach are working then I suspect you're plugged into an electrical outlet
__________________
2016 Newmar Dutch Star 4369
Newmar Owners Club
USAF 1966-1969,- Law Enforcement 1969 - 2003, Unemployed (retired) since March 2003
LJowdy is offline   Reply With Quote
Old 01-12-2019, 05:46 PM   #9
Member
 
rte154's Avatar
 
Join Date: Nov 2016
Location: Illinois
Posts: 38
I agree you will get a good spark when making the last connection. The part that concerns me is there was no batteries in house bay when you got it. I have suspicions that some one has added some jumpers across the boost solenoid or somewhere else in system in order to operate with just the chassis batteries. Take a close look at system for any tampering and maybe a little help from an outsider wouldn't hurt.
rte154 is offline   Reply With Quote
Old 01-12-2019, 06:32 PM   #10
Junior Member
 
TMt2's Avatar
 
Join Date: Jun 2018
Location: Tampa, FL
Posts: 9
For LJowdy...no...not plugged in to AC source.

For rte154...great suggestion! I hadn’t thought to go there. I will trace the primary coach battery cable pathway and look for a “modification.”
__________________
TMT2
2006 Coachman Cross Country - Freightliner) 384 MBS (Cummins 300 DP/Oman 5.5 Diesel)
Toad: 2016 Mazda 3 on dolly
TMt2 is offline   Reply With Quote
Old 01-12-2019, 07:37 PM   #11
Senior Member
 
Join Date: Jul 2014
Posts: 16,515
There should be a boost switch on the dash that controls a large solenoid.

Having someone flipping it on and off, while you listen, may lead you to it. That solenoid is the point where house and chassis batteries meet.

See if the cables are tied together or the solenoid is activated.
twinboat is online now   Reply With Quote
Old 01-12-2019, 10:59 PM   #12
Junior Member
 
Kickstand's Avatar
 
Join Date: Feb 2017
Location: Oakland, CA
Posts: 28
Quote:
Originally Posted by TMt2 View Post
When I connect the coach feed cables (house bank) neg to neg battery 2 and pos to pos battery 1, I get BIG spark on Pos (coach cable) touching pos post on battery
It looks like you’ve gotten some feedback on your question, but I did notice your statement here saying you got spark on the pos post, meaning you hooked that up last. It’s generally best practice to hook up your pos first and then neg. [and when disconnecting, reverse order and take off neg first, then pos.] The reason for this is safety; it’s quite easy, particularly on RV cramped quarters, to hit some metal with your wrench when monkeying around in there. If you do this from the positive side while the negative is still attached, it will create a short, spark like the 4th of July, and can even fuse the wrench to the chassis. This won’t happen from the negative side, and then once that is off and you go for the pos, accidentally hitting the chassis doesn’t complete a circuit. Even better is to have a cut-off switch that you open before connecting the battery leads. You’ll get a spark when you close the cut-off switch after everything is hooked up, but having the spark away from the battery won’t potentially ignite any hydrogen (less of an issue with AGM, but still good practice.) It’s the same principle as connecting the negative jumper to the dead car’s frame instead of the battery terminal directly- as the spark will be away from the battery and lessen the chance of a mini Hindenburg. Good luck tracking your circuit issue.
__________________
2017.5 Outlaw 29H Class C Toy Hauler
Suzuki DL650 “Wee”-strom
Two Chihuahuas
Kickstand is offline   Reply With Quote
Old 01-13-2019, 04:24 AM   #13
Junior Member
 
TMt2's Avatar
 
Join Date: Jun 2018
Location: Tampa, FL
Posts: 9
Thanks Kickstand...true-safety first.
__________________
TMT2
2006 Coachman Cross Country - Freightliner) 384 MBS (Cummins 300 DP/Oman 5.5 Diesel)
Toad: 2016 Mazda 3 on dolly
TMt2 is offline   Reply With Quote
Old 01-13-2019, 04:27 AM   #14
Junior Member
 
TMt2's Avatar
 
Join Date: Jun 2018
Location: Tampa, FL
Posts: 9
Thanks twinboat-I’ll do that once I’ve eyeballed where those cables go...the PO could have modified the circuit?
__________________

__________________
TMT2
2006 Coachman Cross Country - Freightliner) 384 MBS (Cummins 300 DP/Oman 5.5 Diesel)
Toad: 2016 Mazda 3 on dolly
TMt2 is offline   Reply With Quote
Reply

Tags
battery



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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Battery - connected house batteries to both house and engine. Engine battery removed. MMMZ Class A Motorhome Discussions 37 06-07-2018 11:38 AM
House Battery Hookup dlevell Class A Motorhome Discussions 2 04-09-2014 08:33 AM
HELP.. with battery hookup buck454 Class A Motorhome Discussions 28 08-26-2012 08:39 PM
50 amp hookup in the house MyLife Thor Industries Owner's Forum 12 09-17-2007 08:14 AM
Help! Battery hookup problem!! carl1949 5th Wheel Discussion 4 01-01-2007 06:40 AM

» Featured Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 10:26 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.