Help! ?climate control fan whine
 

Hi.
New to the forum, and new to DIY maintaining my e53 X5 :thumbup:
Just changed oil, filter and replaced a leaky expansion tank...:D

Trying to figure out the cause of a pesky whine...
Approximately 3Hz
Not always there
Seems to be coming from the central air vents, but shutting them off does not change the whine
Seems to start up when the car brakes or turns to the right and sometimes goes away with accelleration
Whine goes away completely when the climate control fan is turned off (fan speed to zero).
Noise does not change with turning AC on and off
Noise does not change with recirc/auto/external air change

I'm assuming it has something to do with the blower?? something else?
Anything else I can inspect without taking apart the cowl?

Thanks. I will check this out.

If you have the automatic hvac panel, there's a small aspirator fan that draws in air. That could be your problem. See this link.

BMW Climate Control Diagnostics: Resolving Any Cooling System Problems First Speeds Repairs