[T2] Help to enhance my AUX battery diagram before we burn alive !

[Christophe Guilbert]

Hi,

I am adding a new Aux battery and draw a diagram to do so.  I really 
would appreciate if someone review it to see if I am doing something 
dangerous, enhance the safety or if it could be done differently (and 
more elegantly)

Here is the diagram:
http://mondale.ucsf.edu/download/secondary_batt2.pdf

The feature of rewiring is to select which battery and I to use for all 
my appliances and I can start the fridge on the AUX battery when the van 
is not running.

Basically , I have my Aux battery wire going to the dash board to 
provide the interior light , cigarette lighter and radio.  The interior 
lights, cigarette lighter wires was "repossessed and diverted" from the 
main fuse panel S8. The Aux battery wire (in the dashboard) is going 
back to the Aux battery compartment trough the regular fridge/LED panel 
relay (C in my drawing).
I have a switch S1 which control the relay B , relay B can select if the 
current flowing to the fridge/LED and appliances panel is coming from 
the main or the AUX battery. This way I can select which battery I want 
to use for my appliances. Note that the AUX battery is used by default.
Switch S2 is here to override relay C (fridge relay ) to have the fridge 
working on the Aux battery when the engine is not running , it is also 
light up a strong red light in the dashboard to remind me that the 
fridge is running on the aux battery. This is practical if you are doing 
grocery and don't want to switch to gaz. the trick is that when the 
fridge is not working , the LED panel is (that's the design of relay 
C),  so I use the +12V out of the LED panel post to energized relay A 86 
terminal.  I trigger it by the switch S2 through Tem 85. Note that the 
S2 switch is using ground line.

If any one could be kind enough to tell the weakness of my design and 
how to fix it. I especially would like to emphasized where to add more 
fuse to make it safer.

Thanks and sorry for any eventual headache following my diagram.

Chris