What's this plug?

[sweetaswesty]

I'm tidying up the wiring behind the dash while it's out. I thought I labelled everything I disconnected but there's this strange plug left over. I'm pretty sure it's the plug for the original radio? The blue grey wire comes in from the loom and goes out again through the connector to daisy chain to the cigarette lighter plug, as nothing else seems to be connected to anything I'm guessing that's why it was left in place?
The red tape in the pic is hiding two cut red wires and a cut brown wire which seem to have been diverted to provide battery and ignition power and earth to the radio that is/was attached.
Does any one know the function of the blue/ grey wire which is daisy chained to the cigarette lighter? Is there any reason why I can't just cut this plug out and then connect the two blue/grey wired together.
Also what is the two pin connector for?
Thanks for any help/ advice!
Here's a pic:

[Robsey]

That is a radio connector.
The reds are battery live.
The brown is ground.

The other wires -
the grey / blue wire on its own should be for illumination.

[Robsey]

I'm pretty sure it's the plug for the original radio?
Yes it is.

The blue grey wire comes in from the loom and goes out again through the connector to daisy chain to the cigarette lighter plug,
That is for illumination.

The red tape in the pic is hiding two cut red wires and a cut brown wire which seem to have been diverted to provide battery and ignition power and earth to the radio that is/was attached.
Yes - that makes sense.

Is there any reason why I can't just cut this plug out and then connect the two blue/grey wired together.
No reason - that will be okay to do.

[sweetaswesty]

Brilliant - thanks so much!

[Rascal]

The Two pin connector is for the speed sensing volume control relay from the original VW gamma Radio. Which my bluestar had and caused some confusion as to whether I also originally had cruise control as it connects to the speed sensor on the speedo. There are some images in the cruise control post of mine

[Robsey]

I had a good look through my notes.
The pins numbers and wire colours are.

ALL VW ISO Pins Layout.

[ 2 ][ 4 ][ 6 ][ 8 ]
[ 1 [] 3 ][ 5 ][ 7 ]

T25 Listing. On (early) mono radios, where only a single dash speaker was used.

Pin 4 - Red - 12 volt live feed.
Pin 6 - Grey / Blue - illumination wire.
Pin 7 - Red - 12 volt live feed
Pin 8 - Brown - Ground Feed.

It shows -
blue / white - dash spesker audio +
Brown or brown / black - dash speaker audio -

On later Alpha / Beta / Gamma stereo radios
This is how I would wire up the radio.

Note the ignition live feed to pin 4, and the permanent live feed to the security code memory on pin 5



The wire colours for the speakers are "standard" aftermarket colours, as the colour scheme changes on various models and years

The wire "colours" are those reported to be for very early VW ISO wiring.
The two letter codes that stand for the German nane of the colour, would be the T25 version.

Also ignore the fuse number 55.
Because I chose G2 or G5 for ignition controlled live, it is protected by fuse 18.

[Robsey]

This is the official Bentley layout and colour scheme for a 1990 vehicle.



Plug T8 is the radio power connector.
Plug T8a is the radio speaker connector.

[Robsey]

If I was wiring this from scratch for a non-VW radio,
I would use my coloured ladder diagram, but miss out the security wire on pin 5.

On normal after market ISO plugs, this is not used.