Been looking at Polo and Golf wiring diagrams.

Is upgrading to a 2 speed radiator fan from a single speed fan as simple as replacing the radiator thermal switch with a 3pin one with 95 and 105 degree normally open contacts and fitting the fan from a post 1987 Golf or post 1990 Polo?

There's only two contacts in the single speed plugs, so you'll need to add a wire and terminals at each end.

When I did it, I just chopped the plugs and soldered on spade connectors, but if you're getting precise, I'd imagine http://www.vehicle-wiring-products.eu have got the bits to add another connection or replace the plugs.

can rob all the parts from most golf mk2 (not 16v )

the little bit off loom comes off

Cool thanks.

So I bought a 2nd hand 3 pin 2-speed fan switch off eBay.

It's a 191959481A from August 1991 so Golf Mk2 era.

But does it need an o-ring where it screws into radiator?

Found it I think - maybe a N0438083 29x22 sealing ring.

yeah they have a brass ring...you can use the one off the old switch

avs car parts has new switches for about £8 or so...put one on the g60 a few weeks back