I was looking at a way to hook the aux and vehicle batteries of the Westy
together.  I have a charger set up on the aux batt, so that it gets charged
whenever the vehicle is plugged in.  I would like to connect the two so
that the vehicle batt can share in that charging when needed.  Or let the
aux batt boost the vehicle batt when needed.  So I thought, there's already
a relay in place to do this.  How about a little switch to energize the
coil on that relay?  I tried applying 12V to the blue wire and that did the
trick.  So then I started to find a switch to install for the purpose.  Now
I am thinking about where that 12V is going to go when it also travels back
down the blue wire to the alternator.  Is this a bad idea?  Thanks for any
input.

Edward