Date: Sun, 12 Dec 2010 09:56:48 -0600
Reply-To: Alan Felder <dieseldoofus@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alan Felder <dieseldoofus@GMAIL.COM>
Subject: Wiring in a new Stereo Unit
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last weekend, before having some bodywork done, I decided to replace the
in-dash stereo in my 82 Diesel Westy. I had already wired part of the
new harness together some time ago, then recently ran new (with four
conductors) speaker wires to the rear. The only thing left was to wire in
the power. These new stereo units need constant power from the battery so
that the memory of all of your settings remains intact, and also I wanted to
be able to have the stereo operative with everything else (like door
buzzers) off and no key in, etc. I bought a unit with a remote control so I
can operate everything from the bed position. With a detachable face, I
presumed that by removing the face the only draw would be the memory
sustaining load, and not the LED glowing at the ON button on the faceplate.
I did not have time that day to test this.
The next day, I took the bus to the bodyshop and had a dent repaired. They
had it until yesterday at noon and when I came by to get it they said "we
couldn't start it without a jump this morning". Well the battery is pretty
new so I suspected the recent wiring. After jumping it, got it home and
pulled the battery ground strap. Found a constant 0.7A draw, which I knew
was more than the clock. So went to the power source I had chosen at the
back of the european power outlet and found a 0.69A draw. Bingo - even
without the face plate on, this unit at least draws enough power from the
battery to drive it dead after a few days. About like leaving your dome
light on.
Solution was to insert a switch leg into the amp power lead, to a dash
mounted toggle switch. Now with the clock and the memory sustaining power
there is a 0.02A draw with the new switch in the off position. So now I can
leave the faceplate on and just use the switch. The faceplate is the "pilot
light" so I can tell if I have left it on. Hopefully, this slight draw will
not pose a problem even if I leave the bus parked for a week.
By the way, the back of the european power outlet is a very handy place for
obtaining constant power. It's on fuse 9 which is 16 amp without much else
on it. Most of the 16 amps is for the power outlet. It's also readily
accessible with a male blade on the back and in the area of the stereo.
Since I have a diesel, and have removed the Eberspacher heater, I used the
hole in the dashboard left by the heater control. So, it's unobtrusively
next to the cold start knob.
Don't know if all of these new stereo units draw this much power when in the
"off" state, but it doesn't seem possible to determine until you have wired
it in, none of the manufacturers seem to publish this fact nor the actual
draw.
--
Alan Felder
Austin TX
82 Diesel Westy
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