which harness is best

[Larry C Leung]

Ed, 

To answer your question directly, it won't.

Howeverm the common ground limits the amount of current
that can be carried to (okay, most would think "leave") the 
light assembly, the limit being that the wires to the common 
ground INSIDE the assembly are current limiters.
In addition the connector itself (standard metric 6 mm spade), 
limits current carrying capacity. 
If Audi intended higher wattage bulbs in 
the assembly they would've 1) provided separate grounds
for each set of filaments (i.e. 2 grounds), and 2) given us
metal or plated glass reflectors rather than the thermally
less stable vacuum plated plastic reflectors, which risk 
delamination at higher temps. 

The overall problem is, with a common ground, separate
relays for the +12V to the bulbs still results in the ground
wire carrying ALL of the current fore each lamp assembly. 
Since the typical potential is 200W/side (~17 Amps, at steady
state), that's alot for even 12 ga conduit covered wire. Add to that
the start-up current (don't know what the extra draw is for this),
and you've got marginal wiring for the ground side. 

LL - NY

> Date: Mon, 15 Nov 2004 14:23:52 -0500
> From: "Edward R. Wendell IV" <erwendell at mac.com>
> Subject: Re: quattro Digest, Vol 13, Issue 41
> To: quattro at audifans.com
> Message-ID: <E2863141-373B-11D9-9949-00039305D19A at mac.com>
> Content-Type: text/plain; charset=US-ASCII; format=flowed
> 
> I've been following this thread but I don't understand this. Why 
> would 
> a common ground connection prevent having individual relays for the 
> 
> power supply to each filament?
> 
> > In terms of extra relays, etc, it also depends upon the access to 
> the
> > back of each individual lamp. In the case of the type 44 turbo 
> lamps,
> > there is only one power connector to the "ground" lead, one for 
> each
> > +12V lead and one for the city lamp. So, extra relays w/rt to the 
> high
> > beam won't help. In the case of the original lister's type 85 
> model 80
> > lamps, this isn't an issue, as there is only one high and one low 
> beam
> > filament. As for relays, there are obviously a relay for each 
> beam, 
> > high
> > and low. I run two complete harnesses for each side, so the total 
> IS
> > 4 relays, BTW, and this also controls the current load 
> effectively
> > increasing
> > current carrying capacity.
> >
> > LL - NY
> 
>