[V8] Climate control head lights

[urq]

... did a bit of digging ...

One thing that came to mind is that the HVAC display switches modes with the 
headlights ... if all you wanted to do was to have the HVAC on full bright 
one way to accomplish this would be to make it "think" the lights never came 
on.  The wire that controls this appears to be at location 444 in the wiring 
diagram ... a GY/G wire that connects to pin 13 of the A/C Control head 
(NOTE: not the programmer).  There's a good chance that if you pull this 
wire the illumination on the CC will be full bright at all times.  If you 
test and find the lights aren't on all the time after pulling this pin, it 
might be necessary to connect pin 13 to ground through a low value resistor 
... say 100 ohms.  I seriously doubt that will be necessary though.

I also tracked down the illumination stuff ... it looks like the "Center 
Console Light Booster" (AKA J166) controls *all* of the lights, even the 
ones in the instrument cluster proper.  Actually, there's one separate 
output that appears to go only to the radio.  This means that trying to 
control the IC and center console at different levels would likely require 
getting another booster module and separating the different lights from the 
common circuit.  Note here that I found a lot of these interconnects occur 
in "welded" connections within the dashboard wiring harnes ... which means 
this would likely be a PITA ...

So ... has anyone actually dug into these harnesses to track down these 
"welded" connections?  I'm pretty sure the ground common (terminal 81) in 
#344 is the source of the weirdness I'm seeing ...

Steve B
San Jose, CA (USA)
----- Original Message ----- 

... my recommendation would be to go through the wiring diagram to figure 
out how the back-light controls are set up.  If you're lucky, the lamps in 
the instrument cluster proper are controlled by the control on the IC, and 
all other lights are controlled by the amplifier module.  In that scenario 
it would be as simple as disconnecting the IC from the amplifier and 
installing a second potentiometer for the amplifier.  If there were lamps on 
the output side of the amplifier which you still wanted to have controlled 
by the main dimmer, you could add a second amplifier, and split the wiring 
for the areas you want separate control.

It can be a bit difficult to track the wiring for the dimmer circuit as it 
goes all over the place ... probably better if you have a printed copy of 
the wiring diagram than the soft copy one.  If someone wants some help 
figuring this out, let me know and I can pore through my wiring diagram and 
offer some suggestions.

Steve B
San José, CA (USA)
>
> Do you mean a resistor in series with all of the IC lights? If so, it will
> have
> to be a big one, and you would never get full brightness from the IC - if 
> you
> ever wanted it.
>
> It will be far easier to control only the CC head if you want it to be
> dimmable
> since it requires far less power - probably less than 1 watt.
> My idea would tie the CC display at full brightness all the time which 
> would
> suit me fine and be easy to do. Nothing more than snip a wire and 
> re-connect
> to
> the 12v supply to the CC head.
>
> Dave
>
>
> Quoting Dave Head <v8q at bellsouth.net>:
>
> > You could put a resister in the line to the IC lights...
> >
> > dsaad at icehouse.net wrote:
> >
> > >If you want, you can identify the wire to the display lighting for the 
> > >CC
> > head,
> > >cut it and tie it to a constant source. I doubt this would interfere 
> > >with
> > >driving and I have considered it myself.
> > >
> > >Dave
> > >
> > >
> > >Quoting Mike Arman <Armanmik at earthlink.net>:
> > >
> > >>>There is a module in these cars that basically runs the "dimmable"
> > >>>bulbs, acting to take the load off the dimmer thingie.  It looks like 
> > >>>a
> > >>>relay (double space), is probably in the aux panel over the drivers
> > >>>knees, and might be numbered 447 919 080.  Might be the problem...
> > >>>
> > >>>-- Huw Powell
> > >>>
> > >>>
> > >>When I read this, the light came on - so to speak.
> > >>
> > >>I've been annoyed by the instrument light/climate control light setup 
> > >>on
> > >>my V8 from day one. If you turn the instrument lights down to where 
> > >>you
> > >>can see the road, the CC head lights go out. If you turn the 
> > >>instrument
> > >>lights up to where you can see the CC head lights, you could place a
> > >>mirror on your lap and use the instrument lights for headlights.
> > >>
> > >>I don't like the idea of fumbling in the dark to set the CC controls,
> > >>and I don't like the idea of raising the instrument light level so I 
> > >>can
> > >>see the CC lights to set it, and then backing the instrument lights 
> > >>down
> > >>so I can see the road again.

_______________________________________________
Audifans V8 mailing list
Send posts to: mailto:V8 at audifans.com
Manage your list connection: http://www.audifans.com/mailman/listinfo/v8
Have an Audi V8 question?  Check the Audifans Knowledgebase!
http://www.audifans.com/twiki/bin/view/Audi/V8
Have a V8 answer? ... Please help others by adding to the KB ... all 
contributions welcome!