If your system is like mine, this is not a broken part -- but the way the system works!
Refer to the block diagram in previous post. The issue is that AC (shore power or generator) will run converter which runs coach DC. If you have a Red Light on your main battery switch, it will come ON. However, the Coach battery will not charge UNLESS the Main Power switch is on.
In other words, the coach battery isolator is only controlled by the Main Power switch -- it does not automatically engage when AC power is connected.
To assure that my coach batteries are charging, I make sure Main Power Switch is ON, then plug into AC power.
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