On this fan the fluid in the viscous clutch is affected by engine compartment temperature which in turn controls fan speed.
E39 aux fan resistor pack.
Make sure this fits by entering your model number.
Tools needed was a 1 4 ratchet 8mm 10mm 13mm sockets 8inch extention came in handy a 3 8 ratchet and a t 45 torks socket bit needlenose pliers and a small pick to drive out the plastic push ins.
Bmw part 67 32 8 371 873 check fit below.
Fortunately the air conditioning is blowing cool sweet air and all is good.
E39 bmw dodgy a c resistor repair 5 00pm friday at 26 degrees c driving home in stop and go traffic mostly stop on the a38 and coming up to the markeaton roundabout.
Auxiliary fan resistor repair kit brand new part with full 1 year warranty.
An additional belt driven cooling fan with a viscous clutch is attached to the engine coolant pump.