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Subject:Re: Dash wierdness, was- Aux Battery.....
From:David Gunning
Date:Sat, 27 May 2006 17:29:43 -0400

Saw my ace VW mechanic today (Reggie's VW Repair and Salvage, Waterford,
Maine) and he pointed-out that a reworking of VW ground wires (cleaning,
refurbishing, reconnecting, and adding extra [BIG WORD WARNING!] superfluous
ground wires, etc.) has led to a scientifically proven bonafide 2% increase
in overall performance of many VW automotive vehicles.  May not sound like
much, but a 2% increase in overall gas mileage, for example, at $3.00 per
gallon, may save the average VW vanagoneer, who gets 15 mpg (like I do) in
excess,  of lemme see: 2 tanks of gas per week  X 16 gallons = 32 gallons X
52 weeks per year =  1,664 gpy X $3.00 ger gallon = $4,992.00 per year in
total gas consumption, amounting to a total gas savings of nearly $100. per
year,  per year.  (providing my arithmatic is accurate)

That's enough for a triple lobster dinner for you and your honey, and your
2.5 kids at Maine's finest seafood restaurant.

Which, from my way of thinking, is not too shabby.

Dave

davidgunning@pivot.net

----- Original Message -----
From: "Mark Drillock" <mdrillock@COX.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, May 27, 2006 2:32 PM
Subject: Dash wierdness, was- Aux Battery.....

> As I have pointed out before, one of the weaknesses of the Vanagon that
> shows up more all the time is the dash grounds. VW connected a lot of
> unrelated stuff in the dash to the same ground wire. When that ground
> wire connection develops corrosion over time, strange things happen and
> can drive us crazy. In particular, VW should have kept the cig lighter
> socket ground isolated from the rest. Of course way back then, few
> people used the cig lighter socket for much of anything except
> occasional light of a cigarette. Now we tend to have other stuff plugged
> in and powered up by that socket much or all of the time.
>
> With a weak connection at this one common ground point, the various
> circuits that use it can get a bad ground reference or even have current
> flowing backwards in some wires. The stuff in the instrument cluster
> needs a good ground. Not having it can cause indicator lights and the
> temp and fuel gauges to misbehave.
>
> Mark
>
> Tom Salicos wrote:
>
>> A few weeks ago I passed on what I now believe is not good advice about
>> feeding the Fuse 3 position on the fuse panel to power the radio, westy
>> and dome lights.  I found somebody's post on doing that and I thought it
>> was really slick, but have since had an experience that caused me to
>> change my mind.
>>
>> I ran a 10 gauge fused wire from the aux battery under the carpet, up to
>> the fuse panel.  Then I intentionally blew a spade fuse and soldered the
>> wire to one spade of the ex-fuse that was now a plug.  This ran the
>> radio, Sirius receiver, Westy and dome lights okay.  In fact I ran the
>> radio all day while working in the yard, just to stress test my new aux
>> battery a bit.
>>
>> Unbeknownst to me at the time, the aux battery was not getting charged
>> when I drove.
>>
>> I drove to work and the radio started cutting out.  Then wouldn't work at
>> all.  Then on the way home, on that warm but not hot day, my coolant LED
>> started flashing.  My IR meter said coolant temp was okay and the burp
>> tank level was good.  So I finished the trip home.
>>
>> I checked the voltage on the aux battery and it was down to 6 volts.
>> I'll speculate that the circuit that fires the high coolant warning uses
>> a reference level derived from Fuse 3 voltage, and lowering the source
>> voltage caused the overtemp warning to fire way too low.
>>
>> I fixed the charging problem and got the aux battery back to snuff.
>> Would re-source the audio power later.  I had trouble clearing a code
>> from the Subaru ECU so I decided to disconnect the main battery ground
>> and do it the easy way.  Code didn't clear.  Hmmm.... Seems lots of stuff
>> comes off of Fuse 3 and feeding it as I did puts two different sources of
>> power under the dash.  Not healthy I think.  Yes, I should have checked
>> the Bentley, but hey, I read the tip on the Internet, so it must be good,
>> right?
>>
>> I have since connected the radio and Sirius up properly.  I also have
>> installed a switch that allows me to run the audio equipment when the key
>> is off.  Diagram for that is here:
>>
>> http://www.salicos.com/images/AudioHookup.jpg
>>
>> I am also working on an aux battery web page.  The scholarly dissertation
>> to date is here:
>> http://www.salicos.com/SecondBattery.htm
>>
>>
>> Have a happy Decoration Day !
>>
>> Tom Salicos
>> '87 Syncro Westy EG-33
>>
>