VW Electrics Haynes wiring diagrams

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Possiedon: Hi, Hot on the trail of my faulty wipers (and now heater switch as fog light switch).

I now suspect that there is a +ve feed problem. I have checked the fuses and also all the switchs work if I send them a +ve from a different feed... I've traced the fault back using Haynes to the fuse box area... more specifically something marked as x...

At the top of the diagram there are 4 lines marked

30 ----

15 ----

X -----

31 ----

can anyone tell me what these mean? I need to track down X.. ?

Syncro G:

30 - Permanent live from battery terminal

15 - Switched live from igniton switch (also live when starter is running)

X - Switched live, works only when key is in the run position, not the start position. This is for high current stuff like headlights, fanmotors and heating elements and reduices the load on the battery when starting - those circuits don't apear to stop working when you run the starter because of voltage drop, they stop working because they are actully turned off.

31 - Earth. Theres also an earth at the bottem of the page.

If you follow the lines long enough you can see where they are powered from and link back to the battery. For the X and 15 wiring look at the igniton switch and headlight switch pages.

The headlights are powered off of the X circuit but they actully come off it before the relay which controls anything else powered from X - the line at the top of the page. Hence, if the X relay breaks, all X powered stuff will stop working except the headlights which should still work.


there are marks on the wires like like T3/3 and T7a/6 J52 and then there are some like 4/86 3L and 7/50 What do they mean?

They refer to connectors, relays etc listed at the foot of each page. So 'T3/3' means pin 3 on connector T3. Where you have something like '4/86', that means pin 4/terminal 86. (Terminal 86 is an example of the DIN terminal ID's used by VW, for a list look on Baxters site). If you look at them long enough they should start to make sense !