Date:         Sat, 14 Jul 2007 01:51:04 -0400
Reply-To:     Mark Hersh <markhersh@MSN.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Mark Hersh <markhersh@MSN.COM>
Subject:      Wiring rear speakers - 86 Weekender - long

The internal debate on the engine swap (Subie or diesel?) has reached an
impasse so it seemed time to do make progress with a few little
improvements.  Some PO had removed the rear closets, and we were able to
acquire those last year.  "Monty" had AC originally but the hoses had been
hacked off in the engine compartment and of course with no closets the
evaporator(?) was missing.  The closet we found had no AC component which
was just as well, but had the rear stereo speakers. (remaining AC stuff has
been removed except for the condenser).

Today I removed the in-dash stereo and found four unused wires whose colors
matched up with the wires hanging out of back end of the AC duct (the one
above the slding door) and sure enough, a continuity check reveals they are
the same.  Great!  Right and left and ground.

According to Bentley and my continuity check, the ground for those speakers
is a common ground, that is, the two wires (left and right ground) under
the dash must be spliced together somewhere and only one wire is run
through the duct to the back shelf, where a branch runs off for the left
rear speaker ground.

The problem is that the stereo install/operation guide (PO supplied at
purchase) specifically warns against using a common ground for speakers and
says that each speaker must be hooked up to the ground wire coming out of
the plug/harness/birdsnest coming from the back of the stereo.

I pulled off one of the vents and the front end of the duct work (just
above and behind front passenger seat) and see the wire bundle heading into
the mysterious region above the headliner.  Or is that just a detour before
it heads down the pillar between the passenger door and sliding door?  I
don't think so because I looked in some vent and also a rubber plug and saw
no wire bundle.  I didn't get underneath.

First, I know nothing about car stereos.  WHat would happen if I commonly
grounded the rear speakers as did VW in 1986?  Blow up the stereo or
speakers, I imagine is the worst that could happen.

Second, how in blazes do I get a single strand of 18-20 gauge wire back
there?  It wouldn't be too much trouble to get to the front end of the AC
duct, but then between the headliner and the metal... and how down to the
under-dash?  Does that bundle run down the passenger side windshield/door
pillar?

Any suggestions/help appreciated.

Mark