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RichardT 09-10-2014 05:08 PM

Motorhome 12v wiring
1 Attachment(s)
On my 95 360 I have this under the hood.
I know which one is the Battery disconnect as I have just replaced it.
If you would be so kind as to tell me what the solenoid on the left is, and what it does. And tell me about the blue (battery isolator?) units function.

Also when I bought this someone had connected all the positive terminals to one battery. There appears to be three factory positive wires. I know one will go to the starting battery, at least one to the house batteries, what is the 3rd?

Thanks in advance.


Protagonist 09-10-2014 06:28 PM

I can tell you how a battery isolation module is supposed to work…

Case 1, charging voltage is detected from either the engine's alternator, the generator, or shore power, house and chassis batteries are connected to allow all batteries to charge. Note that this pretty much requires that all batteries be wet-cell, or all batteries be AGM, or else one battery type will get the wrong charging sequence…
Case 2, no charging voltage is detected, but a drain is detected on either the house side or the chassis side, the battery isolation module disconnects the systems to prevent the other system being discharged along with the one that is discharging.

DaveFL 09-10-2014 08:28 PM

Probably if wired correctly selenoid will bypass the isolator and let the two banks of batteries connect to use for emergency starting when starting battery is weak or dead. If you test the isolator you should find house battery on one and start on 3 and alternator on two post.

There should be an emergency start momentary switch on the dash.

RichardT 09-12-2014 07:03 AM

so 1 goes to house battery and the other two go to start battery?

DaveFL 09-16-2014 07:42 PM

Positive cables at the start battery positive connection I have two, at the house battery connection I have 3 positive cables and a couple of small add on wires one for a gas detector don't know what the other small wire is for. So numbers on connections don't match yours but mine is 14 yr old and your 19 yrs makes 31 yrs of owners messing about. and don't forget AS also decided how to run wires not the chassis maker. I don't think you can just look at wires and positively identify where they go without tracing them. I was under the dash last week and I found two sets of wires attached to the back end of half of two switches just hanging behind radio:( couldn't find them in the color coded schematic from AS, can't trace them as they go into a factory bundle.

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