Chassis Battery Draining 2012 itasca Suncruiser 37F

[Armydave]

Hello All,

I know this has been addressed but I need a little more of your expert knowledge. Just replaced my chassis battery about 2 months ago. Something is draining my battery even with the battery disconnect engaged. I know the stairs and the co2 detector cant be turned off. Does anyone know what other items are not connected to the battery disconnect? I have the solar panel on the roof but something is draining the battery faster than the trickle charger can keep up.

Thanks,
Dave

[Morich]

Maybe we can get closer but maybe we can start by bing sure of what the problem??
You mention the chassis battery but are you sure the trickle charger is connected to that battery? Withoutknowing for sure how and what is connected to ecah battery group, we can get into all kinds of confusion.
I think of the solar as normally being conneected to charge the coach battery?

What is "normal" for RV that is new to each owner, is not being quite correct on what is connected to each battery and what is then charging each.
One problem is that as RV get different users, some are often modified to meet what folks feel right for their use.

Excuse me if totallly wrong, but what is common is that the newer user may think something is charging one set of batteries (or both?) but that charge is not connected to the other set.
What I might think would be the the solar is connected tocharge the coach batteries but not connected to the start.
But then where and how is the trickle charger connected?
It may be and somebody may have added a small gizomo called a Trik-L-start, so the devil is in the details of what you may have. Any info that you are sure of on some of those points?

I found this inof on how it was wired when new but that may change over the years, so we have to be alert!

We can use this wire ID chart and the wires often have labels on the ends so we can look at what they were meant to do and where "from" and "to" were:
https://www.winnebago.com/Files/File...ical_guide.pdf

This is the front of the breaker panel showing the breaker for the solar.
\Click these snips to get a better view.



Then if we mentally turn that around and look at the back side, we can find the circuit ID to use the chart! Fourth from right then becomes fourth from left when turned around!!



Long story is that the solar was wired to the coach but when the RV is not running, it is not connected to the start battery and over time that one runs down.
But that is based on not knowing about the trickle charger or any ofthe added parts that you may know about??/

Feel free to correct me if I'm not seeing the whole picture as things can get messy when I guess!

[Armydave]

I purchased this coach from and older couple about 2 years ago with only 3,500 miles on it. I am assuming they didn't alter much from factory settings

Thanks,

Dave

[creativepart]

By having a solar panel on the roof are you referring to the 10w “joke” panel they used to put on older RVs? I have seen a few people swear this tiny thing worked great to keep charged in storage. But for each of those comments I seen dozen’s that said those panels were worthless.

On my coach, I could go about 3-weeks in storage before my chassis battery started to get low. However, since I visit the RV once a month to exercise the generator I could always bring it back up quickly each month. Once the chassis battery passed about 5-years of age it didn’t hold a charge so well. I finally replaced it and now once a month tending again just fine.

But I wouldn’t expect the chassis disconnect to hold even my new battery much more than a month without pulling a cable off of the battery.

[Armydave]

I need to check my manuals but the panel is approximately 12inx24in maybe a little bigger but not too much. I was assuming it was the 100w panel. Maybe I just got a bad battery. I went with the biggest one they had at Advance Auto. About $220. However, the last battery was doing the same thing. I just figured it needed replaced

Thanks,

Dave

[creativepart]

According to your RV’s brochure you have the 10w solar panel, nothing more.

[Morich]

Okay, so we need to do some deeper checking on what the solar is actually connected to.
the OEM setup was for it connected to the coach batteries only and without some other method to charge the chassis/ start battery, it will run down due to some items still connected to it.

I don't believe the solar will be the problem here as I suspect it is only working to charge the coach batteries and if no other charge method or connection, that would leave the chassis side to go flat.
But I did some checking of the parts here:
https://catalog3d.winnebagoind.com/2012/177574.htm

The OEM solar panel does list as 10 watts.


It may not be as much a problem of size but that it is not getting connected to the chassis side!

If you have a meter to test voltage, I suggest doing a small test. Check the coach battery voltage with the solar connected and sunny, then disconnect the solar by flipping off that breaker. If the solar is putting a charge into the coach batteries, I would expect to see a drop when not adding any charge to those batteries.
You may have just enough solar to keep coach and start batteries both charged ---or not. That's still open.
But as a work around until you can arrange some way to keep the start side charged, you can add a temporary wire from any of the positive posts of the ccoach to the positve post of the start and that should bring both up, assuming the solar is adequate.

I don't consider this a good long term solution as it also means that both will go flat if you ever get into losing the solar input for very long!
If you have AC power where the RV is stored, I like adding a small trickle charger as a stand alone item and not using the strap for long term.

[Armydave]

It does appear i do have the 10W solar charger. Is there a replacement for a panel with more wattage ? But it holds for 3 or 4 days and then one night goes from 11.6 to 9.4. with the battery bypassed.

[Morich]

On many RV we don't get the best wire by wire info on the chassis side of things, so we are somewhat limited on looking for exact causes.
But the way batteries may go down can often be very confusing because there are things involved which change the voltage reading in ways that can make them unreliable.
Some of those things are as simple as weather changes with colder weather making the chemical reaction in the batteries work less well and the voltage goes down faster.

But then other things can also come in that we might not notice. One of those which several of us have finally spotted is as simple as a light under the step! The steps are a really more complex operation than I would ever be able to explain. I also have never seen any diagram on how they work. Possibly company secrets?

But things like different weather and whether the door is opened/ closed or the steps left out, does change the amount of power used. If the steps are out and the light is left on, it bumps it up quite a lot. That makes going back to figure out what happed almost impossible?

But for the main problem of the chassis battery running down, the main factor is that it is not being charged. We do know that most RV do have drains much like our cars. The difference is that we don't store our cars for weeks/months at a time and we don't notice those small drains like radio preset and ignition or door locks that can sneak up when we store the RV.
It is a pretty common problem and many of us have found it happening. The solar can't be a solution, since it is not connected to the chassis battery but the coach. Changing to a bigger solar would help but only if it can get to the chassis battery!

[creativepart]

Here’s the thing about those 10w panels. They are so small with such little output that they do not have a solar charge controller. Nor do they have wiring of sufficient gauge to handle much power.

No controller because the output is so small and the voltage so little. Small gauge wire because so little amperage output.

So, they are not upgradable to a more powerful panel. To add a 100w panel you would have to run all new heavier gauge wiring and you’d have to run it to a solar charge controller and then run wiring from that to the batteries.

That’s not upgrading what you have, that’s starting over from scratch. New panel, new wiring and new controller.

[creativepart]

Originally Posted by Armydave

But it holds for 3 or 4 days and then one night goes from 11.6 to 9.4. with the battery bypassed.

I’m not sure if I understand exactly what you are saying. But a battery at 11.6v is really badly discharged and a battery at 9.4v is dead.

If that was the only info I had I’d probably just assume the battery is completely ruined and needs replaced.

But maybe you meant something else by your comment.

[creativepart]

Originally Posted by Morich

the OEM setup was for it connected to the coach batteries only and without some other method to charge the chassis/ start battery, it will run down due to some items still connected to it.

On some models of Winnebago motorhomes these 10w panels are connected to the chassis battery and on others I’ve seen documentation that they are connected to the house batteries. I haven’t checked the Operator’s Manual for the OP to see which setup he has.

[Armydave]

The battery is under warranty. I will replace it and go from there. Thanks for all the info.

Dave

[Morich]

Originally Posted by creativepart

On some models of Winnebago motorhomes these 10w panels are connected to the chassis battery and on others I’ve seen documentation that they are connected to the house batteries. I haven’t checked the Operator’s Manual for the OP to see which setup he has.

Yes, that is where I checked the drawings to find circuit GJ is the solar and goes to the coach battery. With no other connections/mods, there is no connection to the start side.
To me that totally dropped the solar out of the problem as it was likely never really connected, even if it had been usable. Like you've mentioned it was just a new thing and likely never really helped, other than sales!

Snake oil has been around for a long time!

[BobC]

For what it's worth, my 2002 vintage OEM 10W solar panel did a pretty good job of keeping both my two 6V house batteries and the starting battery charged while in storage until it died this past year. I have an Amp-L-Start installed between the house bank and starting battery. Otherwise it would only have charged the house bank. Currently I'm charging via a 50W panel temporarily mounted to my MH's ladder. I am, however, located in the Sacramento area so we get a good amount of sun all year (this winter excepted).

Amp-L-Starts and Trik-L-Starts seem to be no longer available, but similar devices are available. In a nutshell, you install them between your house bank and starting battery so the starting battery will charge from the solar (or other charger) attached to the house bank once it's charged. Some of these devices are bi-directional and can replace a one way device/solenoid that you might already have. I'm sure Morich will have suggestions.

Also, here's a Winnebago publication on "parasitic draws": https://www.winnebago.com/Files/File...%20Systems.pdf

A multimeter with a clamp-on amp post that reads DC amps is a great tool for measuring amp flow. To measure amps with a non-clamp-on meter you have to disconnect the wire(s) to measure amps. This is often difficult or almost impossible to do. Whether you clamp it on the neg or pos cable doesn't matter, you just need to make sure that the clamp goes around all the wires connected to battery post. Often the neg post is less encumbered. On the other hand, if there are several wires connected to the pos post or pos bus bar, measuring the current in the individual wires can help track down the load.

You need to be careful in choosing a meter to make sure it will definitely read DC amps. Sometimes you need to look closely at the picture to make sure there's a setting for DC amps. Here's what I have:

https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1

And here's a less expensive one with a clamp-on DC amp probe:

https://www.amazon.com/Proster-Auto-...45&sr=1-9&th=1

Here's an example of one with a description makes it look like it reads DC amps, but it doesn't -- Don't buy this one:

https://www.amazon.com/Multimeter-El...%2C145&sr=1-10

[Mtn Charlie]

I have the same model and year MH but I keep it connected to shore power while stored. A simple way to find out what is connected to the chassis battery is to disconnect the coach battery, while the chassis battery is still connected, and see what still works. That MH has relays for both, so it is a simple test.