Maybe, but a simple check is to measure the voltage at the fridge relay,
engine running, fridge running on 12 volt setting. The typical Vanagon
alternator gets about 13.5 - 14.0 volts to the battery. The voltage at
the fridge relay may be down by a volt or two from this main battery
voltage and this is just not enough to really charge the aux battery.

Mark

jon wrote:

>And, in my case, the voltage drop problem might actually be a benefit.
>Many AGM batteries only like to be charged to 13.7 Volts (the
>charging system is set to 14.5(ish) volts).
>
>Of course, installing a thicker wire is a good idea. In that case, a
>large diode could be used to drop the 14.5 to the 13.7 that many AGMs
>like. The standard .7 Volt drop of a common diode is close enough.
>
>Jon
>82 Diesel Westy
>
>On Thu, 29 Jun 2006, mark drillock wrote:
>
>
>
>>This has been talked about for years, many have tried it. The main
>>weakness is that the long stock wire runs that supply +12 to the relay
>>reduce the charging voltage enough that the aux battery never fully
>>charges. This problem is made worse when the fridge is running on 12
>>volts at the same time you are trying to charge the battery. For those
>>with the stock battery under the passenger seat, the easy answer for
>>this weakness is to run a wire from the main battery directly to the
>>relay, instead of using the original feed wire from the dash to the relay.
>>
>>Mark
>>
>>jon wrote:
>>
>>
>>
>>>Maybe someone already said this, but I was looking in the Bentley at the
>>>80-85 Westy schematic. Seems an aux. battery could be easily added:
>>>
>>>The Refrigerator 12-volt heater relay could be used as the battery
>>>disconnect (well, if it's big enough). Simply connect the aux bat (through
>>>a fuse) to terminal 30. Move the connection from terminal 87 to 30 (this
>>>supplies power to the water pump, LEDs, etc) are you are almost set.
>>>
>>>The center light would probably need to be wired into this system, instead
>>>to the door/courtest light circuit. You'd also want to wire your stereo
>>>into this circuit.
>>>
>>>Hmmm, I've got a nice AGM battery just waiting to be wired in. Hmmm.
>>>
>>>Add a trickle charger for winter, and all is set.
>>>
>>>Thoughts?
>>>
>>>Jon
>>>
>>>
>>>
>>>
>>>
>>>
>
>
>
>