E34 Aux Fan not working! Help!

[Eugene Hoe <eugene@xxxxxxxxxxx>]

My auxilary fan on my E34 525i M20 doesn't seem to be working. Its a new fan and I recently changed the
radiator temperature sensor as well which activates the fan. I did a manual by pass of the wires and the aux
fan works fine. However when I plugged it to the sensor like normal, it doesn't come on when the engine gets
hot which is what it is suppose to do!!. Checked the relays as well in the fuse box and everything seems fine.
Anyone got any ideas why the aux fan isn't turning on??. Its defintinely not the aux fan, the switch or the relay.
BTW the aircon is forever ON coz I live in a pretty hot place and no the aux fan still doesn't come on. Is there
some other relay/resistor I need to check?. I did notice as well that the aux fan only runs at high speed, I 
understand that it has two settings, low and high. Perhaps a faulthy resistor??.


TIA.

Rgds,
Eugene
E34 525i M20 
Lots of mods.....

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