So after much research – this is how it works. As far as troubleshooting the wiring goes, I find Haynes diagrams easier than Bentleys…!
If you have a damaged loom in your car, you can either:
** – Note this can work and depends on the damage to your loom and what part of the loom. However if its a broken door loom for example, its likely that the ebay loom will be almost as damaged/worn as yours, and not last long.
This page details the second option. VW still sell the connectors or this post might help, as they actually seem to be AMP/Tyco ones.
TDI club link
The sticky cloth type wire wrap is called Adhesive Cloth Fabric Tesa tape i.e. Cloth fabric Tess tape (ebay)
Other sources of connectors are: Vehicle Wiring Products and PoleVolt
VW sell what they call “repair wire” which is a crimped pin and 6″ or so of yellow wire on the end. You can also buy the pins, and a crimp tool directly and DIY, but good luck.
Excellent lookup of the parts (also in ETKA) is in these sites:
Connector and cable repair
splash-proof connectors
Cable to the fuse box for spare fuses
Connector for the instrument cluster and navigation systems
Overview Contacts / Cable Repair / single line
I’ve copied parts of the most useful page (the last one) and put it here – hope nobody minds!
Connectors_0_5mm PDF
Connectors_1mm PDF
Connectors_2_5_and_4_and_6mm PDF
also – ETKA Electrical connectors list PDF
To change the pins in the connector buy one of these – Terminal Extractor tool!
Use like this – insert as shown, push the extractor tool and wiggle tool & wire: