1. Attachments are working again! Check out this thread for more details and to report any other bugs.

vent not working

Discussion in 'Gen 2 Prius Technical Discussion' started by yups, Sep 11, 2009.

  1. yups

    yups Junior Member

    Joined:
    Aug 18, 2006
    67
    2
    0
    Location:
    Tucson
    Vehicle:
    2006 Prius
    Model:
    II
    Can someone link me to a thread where I might find info on the center vents not working. Is it a vaccuum that controls air flow or is it electronic??
    Thx
    Wth, just in case someone else runs into this problem when its 100+ out. Run the heat all the way up for @30 sec to a minute and then bring the temp down using the MFD. This seems to reset the vents from stuck on defrost to frontal A/C.
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,200
    6,464
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    I suggest you consult techinfo.toyota.com which is a subscription website that provides official Toyota repair manual info. It sounds like your problem will not be easy to fix.

    Any motors in the A/C system will be electric, not vacuum-operated. Since the Prius engine does not run a portion of the time, there isn't a continuous source of vacuum that can be relied upon.
     
  3. richard schumacher

    richard schumacher shortbus driver

    Joined:
    Mar 27, 2004
    7,663
    1,038
    0
    Location:
    United States
    Vehicle:
    2004 Prius
    Model:
    N/A
    So, if you go to the Climate display and manually command the midlevel vents to blow, they don't? And the thumbwheel control below each vent is set to open, not closed? Just checking :_>
     
  4. yups

    yups Junior Member

    Joined:
    Aug 18, 2006
    67
    2
    0
    Location:
    Tucson
    Vehicle:
    2006 Prius
    Model:
    II
    Yes And Yes.
    I edited the original post to say I fixed the problem by raising the temp to full heat using the MFD. I then let it run for a few(@30 sec) and then I lowered it to cool with the auto A/C on and it resolved. For some reason the center vents would not work regardless of my attempts to adjust them with the MFD. Its as if they failed to respond when using the MFD. I assume that was overridden when I adjusted the Temps thereby making the computer automation make the changes from heat/defrost to full A/C. And to think I started to pull the dash apart.
     
  5. pribor

    pribor New Member

    Joined:
    Nov 12, 2009
    1
    1
    0
    Location:
    NJ, USA
    Vehicle:
    2005 Prius
    Model:
    N/A
    I hope somebody knows how the vents are routed in the Gen2 Prius. I just recently bought a used 2005 and discovered that the middle two vents next to the center stack are not blowing any air. The ones on the outside, next to the windows blow perfectly fine. The dial at the bottom of the vents are open and I even pulled out the middle right vent to inspect the mechanism and everything is working fine and there is no blockage at the front of the vent. There is simply no air coming out of the middle tubes at all.

    Is there a valve somewhere within the vent tubes that separates the middle/center vents from the outer vents? If not, there must be something physically obstructing the vents at that junction (a mouse nest perhaps?). Can anybody post a vent diagram or explain how I can get at the valve or junction where the obstruction might be?

    I did try putting the temp all the way up and down as suggested on this thread a few times for a few minutes each and it made no difference to get airflow coming out of those vents.

    Thanks for your help!
     
    PriFi likes this.
  6. 2009Prius

    2009Prius A Wimpy DIYer

    Joined:
    Mar 25, 2009
    2,705
    510
    63
    Location:
    USA
    Vehicle:
    2009 Prius
    Here is a diagram for 2009. I think 2005 should be similar. There is a damper (positions numbered 19, 20, 21 in the diagram) that regulates air flow out of the center vents. Good luck! :)

    2009 Prius AC vents dampers modes.gif
     
  7. frayz

    frayz Junior Member

    Joined:
    Jun 25, 2010
    33
    5
    0
    Location:
    Mobile, Al
    Vehicle:
    2008 Prius
    Model:
    N/A
    Anyone else have this problem and fix it? Mine just started doing this and tried the heat/auto a/c trick...
     
  8. Bobdallama

    Bobdallama Junior Member

    Joined:
    Sep 16, 2013
    10
    0
    0
    Location:
    Athens, GA, USA
    Vehicle:
    2007 Prius
    Model:
    ----USA----
    Bumping in hopes that someone knows or can suggest a possible cause and/or solution...2007 just stopped blowing through ANY vents, temperature or level selector does nothing to correct it. Also, the defrost has no flow either...starting to get cold and could really use my heat, which was working perfectly as of a few days ago
     
  9. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    338
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    If there is no flow at all, then it sounds like your blower motor has stopped working, which is different from what is happening in this thread. It is a common problem. The blower is behind the glove box and is accessible without too much problem. Try giving it a decent tap with a tool and see if it comes back to life. The brushes get worn or stuck with these, and a good blow often will reseat the brushes on the commutator. If you are handy, the brushes can be replaced. Used blower motors are available also.
     
    Bobdallama likes this.
  10. Bobdallama

    Bobdallama Junior Member

    Joined:
    Sep 16, 2013
    10
    0
    0
    Location:
    Athens, GA, USA
    Vehicle:
    2007 Prius
    Model:
    ----USA----
    thanks for the quick reply. it seems to have been happening intermittently. maybe it is just the brushes getting worn. is it similar to how you can bang away on a traditional cars' starter and get it to kick in? I'll try this tonight...thanks again!
     
  11. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    338
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    Yes, brush type motors have a period of intermittency before stopping altogether. If it is used often, a replacement motor will be needed at some point.
     
  12. defrankond

    defrankond Member

    Joined:
    Apr 30, 2010
    217
    23
    0
    Location:
    North Dakota
    Vehicle:
    2010 Prius
    Model:
    IV
    i actually had this problem when i bought my prius. the actuator motors were stuck. had to take the lower driver side dash off to get to the air box, took the leavers and actuator parts off gave them a good cleaning and lubricated them really good. have not had a problem since.
     
    PriFi likes this.
  13. sdfor

    sdfor Junior Member

    Joined:
    Jun 11, 2014
    1
    0
    0
    Location:
    nyc
    Vehicle:
    2009 Prius
    Model:
    N/A
    It happened to me this week, June 2014, on a 2009 prius. The 2 center vents stopped blowing. Toyota said, there is not a second blower, just that the dampers are not opening. Toyota opened the dash and cleaned everything and it is working. They say that cleaning "gunk" is not covered by the extended warrantee.

    So I need to know how to open the dash and get to to the works to clean on my own.
     
  14. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    338
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
  15. PriFi

    PriFi Junior Member

    Joined:
    Mar 12, 2019
    18
    3
    0
    Location:
    HI
    Vehicle:
    2010 Prius
    Model:
    III
    defrankond, can you tell us more details on how you took the actuators off and cleaned them? thanks
     
  16. Debora Lockard

    Debora Lockard New Member

    Joined:
    Jun 12, 2019
    1
    2
    0
    Location:
    Mojave, Ca
    Vehicle:
    2006 Prius
    Model:
    ----USA----
    I thought I was going to have to pull apart the dashboard. Good thing is...I tried the heater thing...waited a few minutes and lowered the temp. Nothing!! Then I just started driving. turned the heat up then down my steering wheel and finally, the defroster shut off and the center vents started blowing air and I was able to finally turned on the A/C. Good thing cause it was 104. Thanks to this site...I dodged an expensive bullet. Thank you all.
     
    MrJamtastic and bisco like this.
  17. wsalopek

    wsalopek Junior Member

    Joined:
    Dec 5, 2003
    70
    5
    0
    Location:
    Morro Bay, CA
    Vehicle:
    2015 Prius Plug-in
    Model:
    II
    Debra you have a Gen 2? Ours is a 2010, Gen 3, and wondering if the same possible fix might apply.

    Also, anyone know what this "fix" works (sometimes)? Is it "gunk" being softened/loosened by the heat?
     
  18. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,331
    15,111
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    The way the servo actuators work changed between Gen 2 and Gen 3, as described in this post.