Date:         Thu, 12 Aug 1999 22:32:40 -0000
Reply-To:     "Jason M. Yasment" <vanagon@NYCAP.RR.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         "Jason M. Yasment" <vanagon@NYCAP.RR.COM>
Subject:      vanagon.com aux battery wiring intructions are NOT valid !!!!!
              (long)
Content-Type: text/plain; charset="iso-8859-1"

OK,
    I had wired up the aux battery per the instructions on the vanagon.com
website.  One problem.  These directions are NOT valid!!!!!!

I'll list the directions on the website and then show my findings with the
'84.

1. Disconnect the battery at the groundstrap.
1a. No Problems here.

2.  Disconnect the 3 red wires leading from the fuse box behind the drivers
seat from the relay terminals.  These wires to the fridge and the cabin
light.
2a.  This is where I ran into problem #1.  Yes one of these wires does run
to the fridge.  The other runs to the display panel that shows your
batteries charge.  These both rin through the fuse block behind the seat.
The light over the kitchen is wired to the starting battery independent of
the relay.  I proved this fact by pulling both wires and turning the light
on.....still worked.  Remember this relay is called the REFRIGERATOR 12-volt
HEATER RELAY and has nothing to do with the kitchen light (ref. Bentley page
97.32b)

3.  Connect these two wires to the positive terminal on the aux battery.
3a.  Yes, this makes sense that the fridge will run from this source.   And
the display panel will show the charge level of the aux battery.  This was
not tested in my situation however.

4.  Run an 8 or 10 ga wire from the + terminal on the aux battery to
terminal #30 on the relay. This terminal supplies current to charge the aux
battery when the van is running.
4a.  What the diagram shows when the relay is closed is that it will charge
from the starting battery, drawing that battery down and reducing it's
useful life.  Then the alternator would charge the starting battery the
energy that was used for replenishing the aux battery.  The starting battery
can only recharge the aux battery with what ever energy it has and will not
fully charge unless you drive for a few hours.  In the mean time you will
only put a substantial drain upon the starting battery and still not fully
recharge the aux battery.  In other words the aux battery is not directly
charged by the alternator in this configuration.
    In the diagram on the referenced page of the Bentley manual it show a
lead going to the D+ terminal on the alternator.  This circuit does not
carry a charge but only half of the trigger current, while the ground is on
terminal 50 of the ignition switch.

Steps 5 and 6. reconnect your ground straps.

For the '86 and newer models, the Bentley on page 97.34a, shows a separate
BATTERY CUT-OUT switch designed for this purpose.





Jason M. Yasment
'84 Westfalia