I`m sure my fan initially cuts in just before the 90 mark and full speed just after, though given the inaccuracies in these dials, thats not much help on yours I suspect.. The green thingy is a resistor so it doesnt matter which way round it goes, if you unscrew it from the fan housing and have a look you should see if its ok or not.
If you have a multimeter, it should be almost a complete short (something like 0.3 ohms) but a visual check should be enough.
Mine had both failed, one had a crack in the resistance wire, the other melted one of the connectors. I rewired them with nichrome wire (300mm of 18swg) and 4mm bolts and various crimp connectors. Should outlast the car as the original wire crumbled away on removing it and the new stuff was hard to bend around the former!