If the fuse is blown replace it and see what happens.
Bmw e46 auxiliary fan relay location.
Fuse box diagram location and assignment of electrical fuses and relays for bmw 3 series e46 316i 318i 318d 320i 320d 323i 325i 328i 330i 330d.
To me it sounds like you re talking about the electric auxilary fan.
While troubleshooting the e46 aux fan is outside the scope of this document i ll point out that the e46 design replaced the individual relays with a speed controller integrated with the fan.
There is no engine driven mechanical fan.
This relay location requires that the glovebox be removed for access.
The bentley repair manual shows the location on page ecl 20.
Bmw e46 electric fan fix and troubleshooting testing fan signal on dme https youtu be rdibbrn3 30.
If the fuse is not blown the most likely fault is the final stage unit or the fan motor.
Bmw models that do have an engine driven fan will also have an electric fan mounted in front of the radiator known as the auxiliary cooling fan.
Various relays in the bmw e46 the first set of relays is located behind the glovebox.
For the bmw 3 e46 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 model year.
If the fan runs erratically continuously with the key removed from the ignition or not at all and the fuse is good the speed controller has.
On all bmw models up through the late 90s the auxiliary or main fan is controlled by one or two thermostatic switches that are mounted into the radiator side or bottom tanks.
The fan is mounted between the radiator and the engine and is the main engine cooling fan.