Mk2 16v radiator fan high speed

[hennie71]

Hi guys.

I'm trying to determine if my old 1988 16v jetta 's radiator fan is working correctly.
I replaced some old hoses and the thermostat and fan switch. If I bridge the contacts on the plug for the fan switch, both the low and high speeds work fine.
When sitting in traffic the low speed comes on when the temp gauge is just a bit over halfway. I had it up to just a bit below 3/4, but I never hear the high speed kick in.

At what position on the temp gauge does the high speed normally kick in?