Results 1 to 11 of 11

Thread: Climate Control Fan Speed Not Working Correctly

  1. #1
    Sport Button On
    Join Date
    May 2017
    Posts
    33

    Climate Control Fan Speed Not Working Correctly

    The fan speed control knob isn't working properly. Only the highest fan setting works. No other fan speeds work. Please tell me I don't need to replace the entire climate control unit to fix this issue...

  2. #2
    DSC Off StuM's Avatar
    Join Date
    Dec 2004
    Posts
    87
    Did you ever figure this issue out and get it corrected? I have the same issue, but only intermittently. Thanks,
    StuM
    2006 FORD GT
    Various Porscheís, Bimmers, Astonís, classics, Superformance...
    2013 M3 Lime Rock Edition coupe (sold)
    2011 Audi R8 V10 Spyder (sold)
    1967 Corvette 427 roadster (sold)
    2013 Maser MC convt (sold)
    2014 BMW i8 (sold)
    2017 Audi R8 Plus coupe (sold)
    2017 FORD Raptor Screw
    2019 Rubicon
    2002 Z8 (2)
    2001 Z8
    2019 911 Turbo S
    1968 Nova SS

  3. #3
    Sport Button On
    Join Date
    May 2017
    Posts
    33
    Weíre pretty sure itís the resistor for the fan. Very common issue on other models as well. The highest setting for the fan works because itís a straight shot from the switch to the fan without going through the resistor. Mine was working intermittently as well. Havenít installed the new resistor as mine is working at the moment and my mechanic has a bunch of my other projects that are more of a priority at the moment.

  4. #4
    The symptoms you describe sound very much like a failing Final Stage Resistor, often referred to as a "hedge hog" due to its spikey appearance. These are known to fail quite regularly in contemporaneous E39 and E46 BMW's, so it is highly likely the cause. I replaced one in my son's 2001 330ci a number of years ago, it is a fiddly job up under the dashboard, I have no idea how inaccessible it might be on the Z8.

    https://www.youtube.com/watch?v=7_D-Ki_Kk2k

  5. #5
    DSC Off StuM's Avatar
    Join Date
    Dec 2004
    Posts
    87

    HVAC fan switch resistor replacement process?

    Quote Originally Posted by boomster View Post
    The symptoms you describe sound very much like a failing Final Stage Resistor, often referred to as a "hedge hog" due to its spikey appearance. These are known to fail quite regularly in contemporaneous E39 and E46 BMW's, so it is highly likely the cause. I replaced one in my son's 2001 330ci a number of years ago, it is a fiddly job up under the dashboard, I have no idea how inaccessible it might be on the Z8.

    https://www.youtube.com/watch?v=7_D-Ki_Kk2k
    .......
    ....So, does anyone actually know where this resistor resides and the actual replacement procedure? Seems it vastly differs on the many BMW model lines.
    Thanks,
    StuM
    2006 FORD GT
    Various Porscheís, Bimmers, Astonís, classics, Superformance...
    2013 M3 Lime Rock Edition coupe (sold)
    2011 Audi R8 V10 Spyder (sold)
    1967 Corvette 427 roadster (sold)
    2013 Maser MC convt (sold)
    2014 BMW i8 (sold)
    2017 Audi R8 Plus coupe (sold)
    2017 FORD Raptor Screw
    2019 Rubicon
    2002 Z8 (2)
    2001 Z8
    2019 911 Turbo S
    1968 Nova SS

  6. #6
    Sport Button On
    Join Date
    May 2017
    Posts
    33
    My mechanic was a master technician for bmw and has a physical copy of the Z8 workshop manual. Iíll ask him to bring it to the shop and see if thereís directions on how to get to it. Iíll report back when he brings it.

  7. #7
    DSC Off StuM's Avatar
    Join Date
    Dec 2004
    Posts
    87

    Success, resistor replaced

    Quote Originally Posted by Z8911 View Post
    My mechanic was a master technician for bmw and has a physical copy of the Z8 workshop manual. Iíll ask him to bring it to the shop and see if thereís directions on how to get to it. Iíll report back when he brings it.
    ...
    Well, I bought an OEM HVAC resistor module online and replaced the faulty unit yesterday. Not necessarily overly difficult, but it was a bit tricky. Had to go through the cabin filter(s) frame housing. Pulled the filters for full, yet tight access. Removed the retaining straps on the curved blower fan housing, moved it out of the way and could then reach down and in with needle nose pliers to pull out the old resistor. (Blue in color and you really need a tilting mirror to get a good look at it. It sits on the lower side of the fan housing, in the very center between the two circular fans. Then plugged in the new one. (Four blade type connectors.) Again, difficult to see and position, so it took a bit of blind positioning and working by feel to get it pushed in and secured. Numerous outbursts of *^%#@_= to help the process at times. Tested the fan speed switch and all was back to normal, so re-secured all the parts and tested underway. No leftover parts and no lost sockets or tools down in the depths of the engine compartment! Good as new! 👍
    StuM
    2006 FORD GT
    Various Porscheís, Bimmers, Astonís, classics, Superformance...
    2013 M3 Lime Rock Edition coupe (sold)
    2011 Audi R8 V10 Spyder (sold)
    1967 Corvette 427 roadster (sold)
    2013 Maser MC convt (sold)
    2014 BMW i8 (sold)
    2017 Audi R8 Plus coupe (sold)
    2017 FORD Raptor Screw
    2019 Rubicon
    2002 Z8 (2)
    2001 Z8
    2019 911 Turbo S
    1968 Nova SS

  8. #8
    Well done! What prompted you to come at it from the cabin filter area rather than from under the dash? Hard to imagine there are any YouTube videos on this procedure for the Z8.

  9. #9
    Z8 Millennial Monster 2112's Avatar
    Join Date
    Oct 2005
    Posts
    1,054
    Fantastic!

    any chance you grabbed a picture or two?
    2000 Red over black
    heavily modified for performance. Although, not to the level of GM's car

  10. #10
    DSC Off StuM's Avatar
    Join Date
    Dec 2004
    Posts
    87
    Quote Originally Posted by boomster View Post
    Well done! What prompted you to come at it from the cabin filter area rather than from under the dash? Hard to imagine there are any YouTube videos on this procedure for the Z8.
    .....
    From the looks of it, I donít think you can access the resistor area from inside the car. Itís sitting right in the fan box, within the engine compartment. I know some other models of BMW do have it mounted on the inside, but not our Z8ís.

    - - - Updated - - -

    Quote Originally Posted by 2112 View Post
    Fantastic!

    any chance you grabbed a picture or two?
    . Will try to grab a few picís next time I open things up to check on things.
    StuM
    2006 FORD GT
    Various Porscheís, Bimmers, Astonís, classics, Superformance...
    2013 M3 Lime Rock Edition coupe (sold)
    2011 Audi R8 V10 Spyder (sold)
    1967 Corvette 427 roadster (sold)
    2013 Maser MC convt (sold)
    2014 BMW i8 (sold)
    2017 Audi R8 Plus coupe (sold)
    2017 FORD Raptor Screw
    2019 Rubicon
    2002 Z8 (2)
    2001 Z8
    2019 911 Turbo S
    1968 Nova SS

  11. #11
    Z8 Millennial Monster 2112's Avatar
    Join Date
    Oct 2005
    Posts
    1,054
    Quote Originally Posted by StuM View Post
    .....

    . Will try to grab a few picís next time I open things up to check on things.
    thanks

    2000 Red over black
    heavily modified for performance. Although, not to the level of GM's car

Similar Threads

  1. Gas cap door now working/Thread isn't
    By EDEZ8 in forum Z8 Chat Room
    Replies: 17
    Last Post: May 21st 2018, 23:33
  2. soft top not working
    By ratacruel in forum Problems, Solutions and Long Term Maintenance
    Replies: 5
    Last Post: April 13th 2010, 19:38
  3. OT- The oldest working gas pump in the U.S.
    By hayvenhurstkid in forum Z8 Chat Room
    Replies: 5
    Last Post: October 15th 2008, 15:06
  4. Rear Control Arms
    By Robert Linton in forum Suspension
    Replies: 10
    Last Post: April 17th 2007, 19:51
  5. Tramlining caused by faulty control arm bushing.
    By macfly in forum Problems, Solutions and Long Term Maintenance
    Replies: 6
    Last Post: August 28th 2003, 17:05