Cats and Audi's frightening electrical design

[Traurig, Scott R]

On the plus side, I was just putting in my radar detector (BEL remote unit)
and fog light mod (stay on with high beams) tonight and I am very impressed
with the execution of the design, if not the design itself. Beautiful access
to the electricals, everything neat and clean, great access to the engine
bay through the ECU enclosure, etc. Getting the A-pillar off to run the
remote laser sensor was a little frightening as it came off with a
tremendous SNAP! :) but luckily it was fine.

Still to do: VDO A-pillar boost gauge, build my adapter cable for VAG-COM
(see www.opendiag.com for the do it yourself version-bought the parts
today), and most difficult, install a scanner into the space where the
ashtray is now. Anyone know how much room is behind the ashtray (depth in
inches)? Also, anyone know how the nav. System audio inputs to the radio
work? All I know are the connector pin numbers, but not what they do. I was
thinking of running the scanner audio into them.

Thanks,

Scott
98.5 A4 1.8TQ


 -----Original Message-----
From: 	Paul R. Cole [mailto:bdssprc at wavetech.net]
Sent:	Friday, 07 December, 2001 23:17
To:	Traurig, Scott R
Subject:	RE: Cats and Audi's frightening electrical design

On Fri, 07 Dec 2001 09:37:12 -0500, Traurig, Scott R wrote:

> Man is it hard to read! I say this from
>the perspective of an electrical engineer, not from that of a copywriter or

Audi electricals = JUNK. ( at least in the older cars)

>someone unfamiliar, as to those types I'm sure it looks terribly well
>organized and though out, with all kinds of helpful references and stuff. I
>just wish they would have organized it as one function per page, as opposed
>to random circuit fragments per page. I had to look at 5 different pages to
>fully understand the fog light circuit! The presentation of the fragment is
>excellent, however :-/
>
>Even more interesting is that there is a lot of unfused switching in the
>car. This is kind of frightening to me because it leaves A LOT of
>unprotected wiring and switching components. For example, the entire
>headlight switch assembly is fed directly from the main power bus. The
>outputs of the switch then go through a number of fuses on the way to the
>lighting circuits. The total power fed to and through this switch is not
>insubstantial, especially with all of us upgrading our headlights. If there
>is a fault to ground in the wiring between the bus and the switch, or in
the
>switch itself, say hello to an electrical fire!
>

Aw shit I was sorta hoping the new cars were better.

If I wasn't a car nut & an EE I'd have long since given up trying to keep my
aging fleet running.
The wiring design in these cars [80's Audis] is second ( in being bad) only
to British cars
of the 70's thru the mid 90's ( well until FoMoCo took over Jag)  equiped
with
LUCAS electrics stuff. You know Lucas- Prince of Darkness.

Anyway I've yet to see the manuals on the newer cars and delve into the
electricals
either- you're report is a disapointment. Oh well I was only looking at
getting
a '91 CoupeQ so perhaps it's just a little better than the 4k's .