Recent Posts

1

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Ante Peros on September 01, 2026, 06:53:39 PM »

Holy smokes guys - you are amazing!!!! We have been dealing with some grandbaby-sitting and had to leave the beast for a bit. We have discussed this whole thing over and over with the various mechanics and your discussion has helped immensly!!!! The cut-off switches are now labeled and we feel so much more confident about which ones are which. It seems logical now. The house batteries were not working when we first started this as the tech had put in new battery cut off switches in the battery compartment and had not connected something - the house battery switch did not "click" - - but also had managed to touch something and drain the batteries. They must have fixed the install and charged the batteries and we are back in business. A whole different switch - the one on the engine for a mechanic to start the engine from the back - has worn a lot and has been slipping which creates an engine comm failure. The new switch has been ordered. I think we are following through on some of these recurring problems and are learning along the way. Better to learn at home and not on the road!!!! Thank You so much!!!!  Ante and Ginny

2

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Steve Huber on August 29, 2026, 02:51:15 PM »

Ante,
I stand corrected. Joel was correct. The 3 battery setup supplies the needed CCA (~2850) which is more than the 2 battery setup speced for the CAT engine (1900-2200). You should be ok with this setup but may want to change back to the 2 battery configuration at the next battery change. Not clear why someone used the Cummins engine hookup for the CAT, but it works.
Sorry for introducing confusion into the discussion.
If I read your 2nd post correctly you said you had no electricity the first day of setup even when plugged in. Is this plugged in to shore power? If so it could be due to a faulty transfer switch. Does the inverter indicate low battery when not working?
Steve

3

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Scott Shearer on August 28, 2026, 11:54:39 PM »

Ante,

Unless someone has reconfigured your battery setup, Frank is 100% correct.

Joel gave you a great road map to prove the usage of each battery bank. However, you’ll have a very hard time tracing the cabling as you cannot easily see the backside of the disconnect switches.

It sounds like you are still having issues related to storing your coach. There is a section in your post of April 22, 2026, that discusses some of the gotchas when storing the later model Patriots and Marquis. The only way that you can prevent battery draw is to disconnect them.

-Scott

4

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Frank Bergamo on August 28, 2026, 11:14:14 PM »

The top cutoff switch is for the house batteries. The lower switch is for the chassis batteries. As I stated above, the top trays are the house batteries, the 4 AGM’s. The lower right compartment are the chassis batteries.

5

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Joel Ashley on August 28, 2026, 10:44:49 PM »

I reckon I’d first try tracing the cables to see where they go, but it sounds like you may not be able to tell which Main Switch (“cutoff”) is which?  On ours the chassis switch is rearmost on the panel, intimating the engine’s position on the coach, but that might not be an assured design on any one coach configuration.  And tracing wires with that many batteries involved may be an intimidating task. 

An option would be to first turn off both cutoff switches, then disconnect the ground cable(s) coming into one of the two battery types;  I’d guess the 1131’s would be handiest since they are all together on one shelf and you should be able to see one good sized cable entering that shelf and attached to the negative post of one of the three.  Commonly, the positive cables will have red tape or coloring on their ends, and negative cable ends are just unmarked/untaped black.  With one (or more) black umbilical removed between battery set and coach and fastened securely well away from any battery post, turn the cutoffs back on.  Try starting the coach.  Obviously if it starts, and you know for certain that the threesome have no large ground wires coming into them, then Steve is correct and the 4 AGM’s must then be chassis set.  They do, after all, rate a good deal of cranking amps.  Approach this task with caution;  if you don’t feel comfortable handling battery cables that can spark, then don’t try it.  Ask a certified electrical tech.

Without actually seeing the setup, I’m shooting in the dark here.  But any of your mechanics could’ve done the same thing, likely much easier than you as a relatively inexperienced coach battery inquirer.  If you approach the cable disconnect experiment, please use care that a wrench or other tool used on the negative cable(s) doesn’t inadvertently at the same time hit a positive post or bare cable.  You don’t need sparks in your face.

Joel

6

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Steve Huber on August 28, 2026, 10:38:41 PM »

Ante,
Based on the CCA the AGMs are your chassis batteries. I can't speak for what the battery installer did re the house batteries but the the 3 of them supply the needed amp hours. But it's your coach so...
Steve

7

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Frank Bergamo on August 28, 2026, 06:05:13 PM »

On my 07’ Marquis, the top two trays are the house batteries. The lower right compartment are the chassis/start batteries. I would think yours would be the same.

8

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Ante Peros on August 28, 2026, 04:04:14 PM »

We are looking at page 23 in the wiring diagram - thank you Steve - but if we look at the configurations listed there are no combination of 3 batteries listed for the house (domestic) batteries.....So going by that we are thinking:
 the 3 smaller batteries for ISX engines must be for the chassis
and the AGM's are for the house.
What the heck is an ISX engine? rats - I just googled it and that is a Cummins engine. We have a cat.
I wonder if there is a way to really figure this out when we use the 2 battery cutoff switches in the battery compartment when we store her....one at a time and try to figure out what power goes off?

9

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Ante Peros on August 28, 2026, 03:06:50 PM »

Dear Joel -
Thank you sooooo much! Maybe it was our own confusion...that created the question. We are learning every day with our beloved "beast". We also have a long running discussion on when the batteries should be replaced. We just, evidently replaced all the chassis batteries (the 3 smaller ones) when we had the Aquahot serviced -all at the same time - but we have replaced the larger batteries independently over the last 3 years at one point or another. We have kept trickle chargers on the big batteries while we have stored her but still seem to have low battery signals when we start her up again- that would make sense since those are the house batteries not chassis. But then we have a long wait for the inverter to begin really working when we set her up again. We check all the batteries and try to make sure they are all charged but we are struggling with that first day of no electricity - even when plugged in - on the first day. Your break down of the battery configuration was amazingly helpful!!! Sincerely  Ante and Ginny

and I just received Steve's post as well - which brings us back to - which one's are which.....we are learning.....

10

Technical Support / Re: 2008 Beaver Patriot Thunder Battery Configuration

« Last post by Steve Huber on August 28, 2026, 02:51:16 PM »

I think the AGMs are the chassis batteries as they supply a total of 2200 CCA (550 ea) which is required for the coach (see pg 23 of the 08 Patriot wiring diagrams). Thus the 1131MFs must be the house batteries. They don’t spec AHs but do show reserve capacity of 195. This converts to 81.25 AHs per battery (AH=(RCx25)/60). 3 batteries at 12V yield 243AH. Converting to the 6Vs required by the house system gives you 486Ahs which meets the requirement per pg 23 of the wiring diagrams.
Steve