Auxilliary Fan Operation.

[Unregistered]

On a 1990 535i, should the auxillairy fan come on with the AC or just when the temp rises? If it should come on with the AC, where is a good starting place to troubleshoot? The car does not run hot at all. Thanks in advance.
Will Ollison
1990 535i
1981 528i
1975 2002

[Bruno]

IT should come on with the A/C

Check fuse # 25 and 27 make sure they are good.
Then you pul the plug out of the right side of the radiator and you have 3 pins in it.
shot the brown wire with one wire (don't remember color) and you should have low speed
Do with again with the other wire and you should have high speed.

If none are working... check if the fan isn't seized up. Older fan tend to seize up.