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Central information schematic?

Posted: Wed Oct 05, 2022 6:41 pm
by DMRK
Does anyone have or know where to get a schematic for the Central Information module? These are no longer available. 928 641 602 04

Re: Central information schematic?

Posted: Fri Oct 21, 2022 7:25 am
by Lowencash
Does this help?
central information.jpg
central information.jpg (180.31 KiB) Viewed 2264 times

Re: Central information schematic?

Posted: Mon Jan 30, 2023 9:54 am
by DMRK
Thanks, that is the part I am trying to find the schematic for (inside the red box).

Re: Central information schematic?

Posted: Mon Jan 30, 2023 11:02 am
by Lowencash
The part number corresponds to diagrams that are applicable to the '83-'91models. If this fits the bill, you can find them attached. The Central Info can be found about 8/10ths of the way down.

Re: Central information schematic?

Posted: Wed Feb 08, 2023 7:40 pm
by DMRK
Thanks but I can't seem to find it there.
Here's what it looks like
Here's what it looks like
IMG_20230131_121525475~2.jpg (1.11 MiB) Viewed 2136 times
.

Here's what it looks like.

Re: Central information schematic?

Posted: Wed Feb 08, 2023 7:48 pm
by Lowencash
DMRK wrote: Wed Feb 08, 2023 7:40 pm Thanks but I can't seem to find it there
Sheet 12.

Re: Central information schematic?

Posted: Wed Feb 08, 2023 7:52 pm
by DMRK
IMG_20221210_162414189 (2)~2.jpg
IMG_20221210_162414189 (2)~2.jpg (1.25 MiB) Viewed 2132 times
This is what it looks like inside. You can see the yellow and black connectors as shown in the red box. I can take the time to trace it all and draw up a schematic if necessary. I'm not sure it's the culprit just yet. Any way it has to sit for awhile anyway, too many projects.

Re: Central information schematic?

Posted: Wed Feb 08, 2023 7:55 pm
by DMRK
That's the central electrics or fuse/relay panel under the passenger foot rest.

Re: Central information schematic?

Posted: Thu Feb 09, 2023 10:31 am
by Lowencash
Last try...

I'm finding this a bit hazy...is it a Central Information Indicator, a Central Electrics module or is it a Central Dash Indicator? The numbers seem to be one and the same for two of these; hence, wrong diagrams. Let's see if I've got it right now.
The diagram below is super clear in the attached pdf.
Central warning diagram.png
Central warning diagram.png (171.76 KiB) Viewed 2116 times

Re: Central information schematic?

Posted: Thu Feb 09, 2023 12:23 pm
by dr bob
There's a "central electrics panel" which is the main fuse-and-relay panel located at the passenger-side footwell. Separately, there's a central warning module that manages the alerts and warnings that are displayed in the gauge cluster. In your electrical "current flow diagrams", the components in the central electrics panel are shown in dot-dashed boxes.

The central warning "computer" is not well documented at all. I'm not aware of a single detailed functional description document for that module, but realistically there isn't a whole lot of smart needed to get things to work properly. The individual warning "logic" is loosely described in a few places in the WSM set, but nothing really comprehensive that I've found. I've redrawn a few sections of the sheets for my '89 S4, mostly to help with troubleshooting things like the HVAC control head. The Central Warning system on mine is a bit more complex than your earlier car, thanks to the digital display, but except for ABS and the trip computer functions, they are also amazingly similar. If you are looking for a replacement central warning unit, good used ones are available from 928 International in Anaheim. In my limited experience though, everyone I know who has replaced the central warning unit due to apparent false warnings has continued to chase them even after replacement. It's almost always wiring, connections and most commonly poor grounds that seem to cause false warnings. Know that the foil backplane of the instrument cluster is a very well-known weak spot in the system. Replacement foils are available for most variations (model/years...).

HTH!