My Syncro has the same habbit - there is two causes of this - first, there
is a small voltage drop everytime you turn something on... but, with mine I
would go from 13V to 12V by turning on the park lights!  Highbeams would
take it down to 10V or so... the problem was a bad ground connection on the
voltmeter - take a multimeter and run it to the battery and compair the
voltmeter to the multimeter - usually a big difference.  Then run a wire
from the voltmeter ground to the neg terminal on the battery, now there is
less of a difference.

At 02:59 PM 23/02/2000 EST, Ken Hunter wrote:
>I found an old posting to the list (1997 or so) that talked about running an
>extra 10g wire from the battery to the fuse panel. This was to compensate for
>a voltage loss  when using high draw accessories like heater fan motor,
>wipers or high watt headlights because of the long length of the wire. This
>was brought to my attention when I installed VDO gauges and the voltmeter
>dropped from 13+ volts to around 11V when the heater fan was placed on high.
>I first thought that maybe my fan motor was going out but maybe this extra
>wire is what I need. When driving at night with wipers, defroster, highbeams,
>and radio on the volts still show 11. Could this voltage drop cause problems
>with fan motors? I know my Skill saw cautions against using a extension cord
>that isn't rated for the load and distance.
>
>
>
>
>
>Ken Hunter
>82 Westy 1.9D
>84 Jetta 1.6D
>89 Mitsubishi van
>
>

--   David Marshall -                    - Quesnel, BC, Canada   --
--    78 VW Rabbit, 80 VW Caddy, 84 VW Westie, 85 VW Cabriolet   --
--       87 Audi 5000 Quattro, 88 2.0L VW Syncro Double Cab      --
-- David's Volkswagen Home Page        http://www.volkswagen.org --
-- Fast Forward Autobahn Sport Tuning  http://www.fastforward.ca --
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