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SJ-Chris's avatar
SJ-Chris
Explorer II
Jul 09, 2018

Fuse for battery disconnect? Converter charger? Need help...

Hello all! I'm having a strange issue that I cannot seem to diagnose.
I have a 2006 Four Winds Chateau 31P Class C RV. I've owned it for 9 months now. I've got 3 new 12V deep cycle house batteries (all purchased 6 months ago). I have not had any issues lately regarding charging, batteries, etc. When the RV engine is on, the alternator is providing 14.1v on the house batteries. When I was plugged in to shore power, my WFCO converter (purchased 6 months ago) was charging the house batteries. When my Onan generator was on, the house batteries were getting charged and everything in the RV works (120v and 12v). Something changed over the last week.

I have a volt sensor connected to an app on the house batteries and I can see that they are fully charged (~12.9v) after a recent 5hr drive. I just put a volt meter on the house batteries and confirmed that there is ~12.9v on the batteries (engine off, not plugged in to shore power, and generator off).

Here's the issue... For some reason (when not connected to shore power) the Battery Disconnect switch is no longer working. When I am not connected to shore power and the generator is off, when I turn the Battery Disconnect switch 'On' nothing happens (...it used to work fine up to just one week ago). Now, nothing happens. And none of the 12v items in the RV (ie. lights, etc) work. I also notice that the Kwikee electric step does not move when I open/close the side door. If I turn on the generator (or plug into shore power), the Battery Disconnect switch seems to be overridden and all the 120v and 12v items in the RV work fine AND the electric step opens/closes perfectly anytime the side door is opened or closed.

I checked all the fuses in the RV house converter fuse box and they are all fine. Is there a separate fuse for the battery disconnect? I don't remember the electric step requiring the battery disconnect switch to be "on" in order for the electric step to work. How does your electric step work on your RV when the main battery disconnect is 'off'?

I also notice now that when I plug into shore power or turn on the generator, nothing changes on the house battery voltage (...Looks like they are NOT being charged). All of the 120v and 12v items on the RV work when plugged into shore power or the generator is on. The AC...the microwave...the electric side step all work when plugged into shore power or the generator is on.

Any thoughts on what I should check? Is there a fuse for the Battery Disconnect (and electric side step)? Could the fuse be under the driver side dashboard? (those seem to be more associated with the RV engine and dash and lights....).

It looks like there might be two independent problems...something wrong with the Battery Disconnect, and the converter charger doesn't seem to be working. Thoughts?

Your help is greatly appreciated!

-Chris
  • See the orange 5 amp ATC fuse in your pic? There is ANOTHER fuse on the bottom side of that solenoid. They have 2- 5 amp ATC fuses and BOTH must be good for the system to operate. To bypass is simple. Use an 8 gauge wire and just connect the 2 large posts on that solenoid. Doug
  • Call me Chris.
    I can help you over the phone.
    I am a retired electrical troubleshooter.
  • Is this a viable short term work-around??? Assuming for a moment that I don't care about having a functioning Battery Disconnect switch by my side entry door, can I just use a properly gauged wire jumper across the two large terminals on this solenoid? If my understanding of how the battery disconnect switch works (providing just a temporary voltage to 'latch' this solenoid on/off) and how the solenoid works (effectively connecting or disconnecting the two thick cables on the large terminals) then it seems like if I wanted to bypass both of them and always have the batteries "on" then I could simply connect a properly sized jumper across the two large terminals. Right??? Please let me know if I am missing anything. There are other wires connected to this solenoid and I'll be honest, I am not sure what they all are or what they all do (...so maybe putting a jumper across the two large terminals would actually be a bad idea...)

    Or is this solenoid more complex? Perhaps it is doing certain things to isolate the charge coming from the chassis alternator when simultaneously plugged into shore power (and the converter/charger is on)???

    Thoughts from you experts??

    Thanks!!
    Chris
  • I continue to learn..... I was reading up more and here's what I learned...

    The wall switch is in fact just a remote switch that goes to a house battery disconnect solenoid located under the rear bed near the converter. Here (I believe) is a photo of that in my 2006 Four Winds RV:


    When I push the battery disconnect switch by my side entry door, I believe I used to hear a "Click" noise. I assume that was coming from this solenoid. Well....now when I push the battery disconnect switch by my side entry door I do not hear any sound at all. I suppose it could be a bad disconnect switch, OR it could be a bad solenoid. Can anyone recommend how I can easily check the solenoid to see if it is working properly?

    I found a replacement solenoid here if needed:
    https://www.amazon.com/INTELLITEC-0100055000-Battery-Disconnect-Relay/dp/B072N8NYN2

    Thanks!
    Chris
  • Does anyone know where I can find a replacement for this switch:




    I have searched online for 30 minutes and cannot find a replacement part. It is for a 2006 Four Winds Chateau 31P Class C. Let me know if you have a suggestion for where to find it. Thanks! -Chris
  • in most cases yes
    the converter-charger is located close to the power center fuse panel
    the batteries are in a remote location
    with batteries disconnected from house, they can not be used and can not be charged from the converter

    the battery separator/combiner is wired directly to alternator
    so batteries charge when the engine is on, regardless of the disconnect situation
  • Old-Biscuit wrote:


    With it failed in OFF position the battery can NOT supply 12V DC to coach, converter/charger can NOT charger battery



    Is this the standard way they work? If the battery disconnect switch is OFF then the converter/charger does not charge the house batteries???

    Thanks!!
  • ELIMINATE electric battery disconnect switch and install a manual twist with your wrist manual disconnect switch. Cole-Hersee, and Blue Seas, manufacture good manual switches. 1 - 2 - BOTH - OFF
  • Battery disconnect is BAD

    With it failed in OFF position the battery can NOT supply 12V DC to coach, converter/charger can NOT charger battery

    When plugged into shore power or on gen the converter is supplying the DC System

    Replace the Battery Disconnect Switch