Re: 2003 X5 (Aux?) Fan Keeps Running


"DJ" <ddjames@xxxxxxxxxxxxxxx> wrote in message
news:VmIsf.61931$6e.24496@xxxxxxxxxxxxxxxxxxxxxxxxxx
> Could anyone suggest a reason why the auxiliary fan in my 2003 X5 keeps
> running even after the engine and ignition are shut off? I presume it's
> the auxiliary fan but don't know for sure. The fan noise is emanating from
> the area where the cabin filter is installed under the hood near the
> firewall. Is it supposed to run all the time?
>
> Tonight the fan sounds as if it's running at a constant speed. On other
> occasions (last night, for instance) it sounded as if the speed varied.
> This observation is based on the pitch of the fan sound. It appears to
> keep running for hours after the engine and ignition are shut off. The car
> has been off about 3-4 hours tonight and the fan is still running.
>
> There doesn't appear to be any way to get it to shut off. Last night I
> started the engine, turned off all interior fans, then shut the engine
> off. The fan noise continued for several minutes (variable pitch noted)
> then stopped. I tried the same thing this evening with no luck.
>
> A Peake Research scan tool reported no codes.
>
> The vehicle is out of warranty, so any help would be appreciated.
>
> Thanks in advance!
>
> ~ Dave
>
>
>

This could be normal operation. The electric fan comes on when the cooling
load is high. As you appear to live in Florida then this could be real.
The fan will run for a minute or two after switch off (wired round ignition)
if you have been taking a lot of power from the engine or idling a lot (e.g.
towing, hill work, just come off freeway or sat in traffic for ages).

If it is staying on all the time or long after switch off then probably the
thermal switch for it needs cleaning or replacing.


.

Relevant Pages

  • 1995 325i overheated
    ... of my car overheating at the wierdest of times. ... fan clutch, thermostat, thermostat cover, fan blades, ... after I shut the engine off, this morning I checked the coolant level ...
    (alt.autos.bmw)
  • Re: 1995 325i overheated
    ... > of my car overheating at the wierdest of times. ... fan clutch, thermostat, thermostat cover, fan blades, ... > The check coolant level warning would sometimes come up on the OBC ... > after I shut the engine off, this morning I checked the coolant level ...
    (alt.autos.bmw)
  • Re: Fan - Suck or Blow?
    ... That's counter to every engine I've seen. ... the air the other direction. ... When I rebuilt this, I didn't take the fan off, nor any of the pulleys. ... A suck fan with closed side doors combined with head down and large rods ...
    (sci.engr.joining.welding)
  • Re: Overheating Supra
    ... I went out Saturday morning and spun the fan with the engine cold. ... the clutch is probably disengaged. ...
    (alt.autos.toyota)
  • Re: Design of a Fan controller
    ... I have some data which says Fan mechanical power Vs Fan speed. ... The specifications give radiator's delta T without specifying whether the fan is off or the speed of the pump. ... (Slower circulating speed exposes coolant in the radiator to cooling air for a longer time, so it emerges cooler _for the same inlet temperature_ but the coolant remains longer in the engine, and so emerges hotter. ... That will keep the engine from damage while you make the measurements needed for a more sophisticated design. ...
    (sci.engr.control)