About a month ago, I mated a trickle charger with a cig lighter plug
so I could plug up the westy electrical socket to a power source, plug
the trickle charger in to the interior 110v socket, and plug the cig
lighter plug into the receptacle on the bulkhead under the seat. No
muss, no fuss, but not quite permanently wired in. That turned out to
be a good thing, as I noticed on a recent camping trip that even with
the charger unplugged from the interior 110 receptacle, the LED light
on the charger glowed when the setup was plugged into the cig lighter
socket. That means that the battery was feeding the charger.

Is there any significant current loss going backward through the
charger? Is it just running the LED, or is it running down my battery?
I presume the proper diode in the proper place would stop this. Can
anyone describe what I should to do modify?

Jim