Club 80-90 Forums

Lots of electrical problems and a naff diagram.

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I can't make head nor tail of the diagram, some things are not numbered and some don't match the description.

I am far from useless at electrics but the mind boggles.

The first fault on the agenda is the alternator.

Currently the wire which should go to the ignition is wired directly to the battery so that it is permanently switched on and drains the battery overnight.

Should the excitement wire go to a relay, to the ignition or elsewhere?

I need to know where that wire is supposed to go and the colour codes.

Does any one know where I can source a diagram for a 1982 T25 CS1600 diesel?

The diagram shown came with the JK manual as a separate sheet.

Thanks in advance ect.

82 1.6 n/a diesel is in the Bentley manual; be aware it's the american version but since VW used DIN standard wiring for the most part it should be pretty usable

Put up a couple of pictures of your wiring

Thanks for that.

One of the photos didn't come out and I have left the diagram in the van which is down the road. I will upload the other photo tomorrow.

What I am trying to find out is whare does the excitation wire go to.
There is a glow plugs relay, maybe it goes to that or to the ignition switch, so many wires which don't attach to anything in the engine bay, that I can't fathom it.

I should think if it goes to the ignition switch there will be a wire in place but I don't know which one.

I should think that when the ignition is switched on the glow plug relay will be live but it must have some sort of timing mechanism to switch it off. Maybe in the relay or under the dash.

Can anyone tell me where the excitation (ignition) wire is supposed to go and the colour codes?

Thanks.

David above...

I can put up some pics of the alternator and the three wires from it tomorrow.

One is negative and goes from the alternator to the battery.

Two are positive and go directly to the battery.

(Battery disconnected over night)

One of the positive wires (thin one) should go to the ignition switch possibly via a relay.

It's been butchered.

Not started on the dashboard yet... It's in a sorry state.

I need to start with the alternator.

Looking at the Bentley manual, there are only three wires from the alternator for the 1982 diesel.

Two fat reds - both go to the battery + terminal.

One thin blue wire - goes to the charge light on the dashboard via three consecutive single pin connectors.
I believe the alternator charge light circuit is often used as the exciter line. So that would be the blue
The alternator is grounded via it's mountings.

If you have a negative wire, it should be brown or a bare braid.

If as you suggest, the alternator is flattening the battery, then I suspect that it is a fault with the alternator or at least the rectifier unit or voltage regulator mounted on the alternator.

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The "ignition" reference is a bit confusing...

The charge light has a +12 volt ignition live feed.
And the return path for the light is the blue wire from the alternator.

When the alternator is at rest, the blue wire is at or close to 0 volts and the light illuminates.

When the alternator is running, the blue wire carries battery voltage and therefore "cancels out" the charge light circuit, thus putting off the charge light.

See if this helps.



BL = blue wire to instrument cluster.
R = Two red wires to the battery + terminal.

The thin lines for the grounding refer to being connected directly and not using wires.

Ignore the line saying starter - it is not a wire. Just a poor location for the label.

Thank you very much Robsey...

I have got the blue wire going to negative on the battery...

That's how it was when I got the van...

Ahhh, Ahhh haaaaa...

I will have a look at that tomorrow and upload some picks...

Thank you very much indeed ...

I just thought - it is a diesel.
If you have a tachometer, then the signal for this comes from the alternator -

Green wire on the W contact.



Blue wire to battery charge light (red led).

Green wire to rev counter

Two fat reds to battery positive.