12v system question

[msgtnobody]

Had a problem with chassis batteries, make a long story short. While testing batteries I noticed that all interior 12v lights, master control panel that shows tank levels and battery power level level were powered by the chassis batteries. the only controls that worked from master panel were slide switches. So I know the slides are working from the house batteries. When I removed the bad batteries and replaced them with new all sytems worked again.  I made sure i did not have house & chassis batteries  switched. I dont know if connections are original because I bought rv used. I am enclosing pictures of battery compartment prior to adding new batteries.  My question is why would interior lights and control panel be using Chassis batteries??

[sstgermain]

The interior lights and stuff should be on house batteries and not chassis batteries.

[richard5933]

Have you checked that solenoid on the back wall to see if it's failed and always connecting you house and chassis batteries?

[sstgermain]

That looks like the jump start solenoid. I think if that failed he would have interior lights on house and chassis batteries.

[msgtnobody]

12 minutes ago, sstgermain said:

The interior lights and stuff should be on house batteries and not chassis batteries.

I know that. That's why I am asking on this forum.

[msgtnobody]

11 minutes ago, sstgermain said:

That looks like the jump start solenoid. I think if that failed he would have interior lights on house and chassis batteries.

That's how I noticed I was having a problem with batteries. The solenoid was clicking. When I checked batteries the house were good but chassis were 6.5v and 7.1v. I took them out and tested them. One was bad other wouldn't fully charge. They were 7 years old. After putting in new batteries no clicking.

[sstgermain]

I guess what you need to do is find out which one of those cables in there powers the house lights and put it on the house batteries. Should be easy to figure out by disconnecting one at a time. Usually slides run on the chassis batteries. Mine needs to be running to operate the slides and levelers.

[msgtnobody]

15 minutes ago, sstgermain said:

I guess what you need to do is find out which one of those cables in there powers the house lights and put it on the house batteries. Should be easy to figure out by disconnecting one at a time. Usually slides run on the chassis batteries. Mine needs to be running to operate the slides and levelers.

Would It be a positive or negative? I had 4 single positive cables connected to chassis batteries and 3 single negative ones. The picture of compartment shows all loose wires while batteries were out.

[richard5933]

Do you have a wiring diagram for the coach? It will show how things were connected at the beginning, before a previous owner moved things around.

Not sure how things in your particular coach are wired, but shouldn't the negative cables all be common to both sets of batteries? If so, then you can install a buss bar and move all the negative wires to that instead of having them connect to the battery itself.

If the solenoid was clicking with weak chassis batteries, then I'd guess that the solenoid was switched on during that time and powered by the chassis batteries. Sounds like they didn't have enough juice to fully engage the solenoid, hence the clicking.

Have you confirmed that your house batteries are good? Might be wise to take them to have a load test performed.

[manholt]

Could you please tell us...make, model, class and year of coach?

[msgtnobody]

2008 Monaco LaPalma XL

[sstgermain]

It would be the positive side

[manholt]

msgtnobody.  

Call Monaco REV Tech dept.  They will  need your Monaco Serial # & VIN #.  Tell them, you want the electrical wiring diagram & harness....you can get it via PDF.   

[kaypsmith]

I know this sounds like a stupid question, but will the coach crank with those batteries out? If so, the pictures look as though someone may have the wrong knobs on the two switches, this would explain everything seeming backwards.

[manholt]

Kay.  You know, nothing is dumb or stupid on this Forum....you may be right.  

[sstgermain]

3 hours ago, manholt said:

Kay.  You know, nothing is dumb or stupid on this Forum....you may be right.  

X2

[msgtnobody]

9 hours ago, kaypsmith said:

I know this sounds like a stupid question, but will the coach crank with those batteries out? If so, the pictures look as though someone may have the wrong knobs on the two switches, this would explain everything seeming backwards.

 

[msgtnobody]

They were the correct batteries I removed. The rv would not start when I removed them 

[richard5933]

Here's my guess...

If the chassis batteries were dead (or nearly so). The solenoid was clicking until the chassis batteries were replaced, indicating that it didn't get enough juice to fully engage. If the house batteries were/are good, that means that the solenoid was getting it's switching juice from the dead chassis batteries. The fact that some of the house systems were pulling power from the chassis batteries is likely what caused the chassis batteries to die early. They are not deep cycle and not designed to be used that way.

If you figure out which circuits belong to the house batteries and put those circuits back where they belong, you'll likely eliminate the problem with the chassis batteries.

[msgtnobody]

That's my next project

[kaypsmith]

With the chassis batteries back in place, take pictures of the setup, then remove the black cable from the right side of the rear post of the house battery bank, then check to see what still works in and out of the coach. The leveling jacks should work, probably need the coach running to test those, the inside overhead lights should not. Oh yes, make sure that shore power is unplugged, otherwise the inside lights should still work if shore power is plugged because they will be getting current from the inverter/converter.