I'm interested in where cable (4) goes.  It seems to disappear into the wing and I can't find it in any of the wiring diagrams.

(1) Orange indicator bulb goes here.
(2) Connects to (3).
(3) The black-white wire comes from yellow connector 3 in the Aux panel. It's for the left-hand-side turn signal.
(4) Has (1) and(2) coming out of it and it disappears into the wing.

If I do a continuity test on (1) and (2), it seems to show that the black and brown are connected together? Does that make sense?

Any help is most appreciated.

Thanks!

Hello Mohammed,

Have you got a Haynes manual for the car - should have been available for your era car. If you don’t - try EBay. 
Could you let us know how you get on please? 
Kind regards,

Gareth. 
 

Thanks Gareth for getting back.

I do have a Haynes manual for the car but it's up to 1990 only - got that from eBay. There doesn't seem to be anything for my particular model or year. I've tried the official Haynes online site too.

All the wiring diagrams that I've found so far, even those in German, don't show that extra cable that disappears into the wing. That arrangement exists for both sides of the front indicators.

Those diagrams have been really useful for diagnostics as quite a lot stays the same, but I can't find any reference to that cable (4). Even those diagrams that are supposedly for an Audi B4 1992, don't show it.

I've even used a borescope to see close to the bulkhead if I can see any cables coming in but it's just too difficult. 🙂

I finally got to the bottom of this.

I didn't notice the small indicator lights on the two front wings! I was so focused on the main indicator lights that I completely forgot about these. And these turned out to be important...

The wiring that goes to the front indicators also goes to the indicators on the wings. When I was doing continuity tests, because the wing indicator bulbs were still in there (and working), the meter saw it as the black and brown wires for the bulb connected together. Had I removed this bulb, the circuit would have been broken and it would have metered as expected.

Edited September 3, 20241 yr by AudiMT